Comprehensive GMC Sierra How to & Troubleshooting Guide

The GMC Sierra is a very reliable and resilient work and play truck. Though not as popular as the people’s favorite Ford F150, the Sierra 1500 and Sierra 2500HD consistently feature in the top five positions across different ranking categories.

You shouldn’t expect any major problems when buying it new or going for a cheaper used unit. Despite this ruggedness, a couple of things could trouble you along the way.

We will give you a comprehensive how-to guide to help you use features to the fullest and a troubleshooting guide to help you figure out common issues. We will tell you how to fix the simplest and advise you on when to take your GMC Sierra truck to an expert.

How to Remote Start a GMC Sierra

Remote start is an excellent feature that lets you turn over your vehicle’s engine long before you get into it. It can come in handy if you want to turn on air conditioning and bring up the cabin to the right temperature before stepping in.

ProTip: Ensure your Sierra is in a well-ventilated area. Remote starting in an enclosed space like a garage will increase carbon monoxide levels, introducing CO poisoning risk.

Does My GMC Sierra Have Remote Starter?

The majority of modern GMC cars have remote start installed from the factory. There will be a dedicated remote start button on the keyfob if your’s has it.

If you have the GMC mobile app (myGMC app), the remote start feature will be active on the app if the truck supports it.

Another way to infer if your truck has remote start is by looking for the hood position switch. The switch monitors if your hood is open or closed. Remote start doesn’t work with the hood open or partially locked.

You can also check your vehicle specifications to see if remote start is listed for your GMC Sierra truck.

How to Remote Start Your GMC Sierra With the Keyfob

Here’s the procedure to remote start your GMC Sierra if you have your keyfob at hand

Press the LOCK button on your key fob
Press and hold the REMOTE START button (circle arrow) for at least four seconds
The turn signals should flash, and the engine will turn over.

How to Remote Start Your GMC Sierra Using the myGMC App

You can control your GMC Sierra and other GMC vehicles from your Android or Apple mobile device as long as you have the GM OnStar Remote Access subscription.

Download the MyGMC app from the App Store or Google Play store
Launch the app and select your region and country
Sign in to your account or create one. Accept the user and privacy terms to proceed.
Select manage vehicles > add vehicle (if you don’t have other cars, you will be automatically prompted to add one
Enter your vehicle’s VIN to add it.
If your OnStar vehicle profiles show that the VIN belongs to you, the vehicle will be successfully added.
Go back to the Home screen and hold the POWER button
The turn signals should flash, and the engine will turn over
A countdown will display on the power button showing how much time of remote start run is remaining

Why Does My GMC Sierra Turn Off After Remote Start?

Usually, your GMC Sierra should run for 15 minutes after the remote start; then, it will shut down. This is enough time to run AC and bring the temperature to the correct range.

If your truck is shutting down sooner than that, then it has a problem. But if it is running for 15 minutes, everything is working as designed.

Some of the things that could make your truck shut down faster include:

Oil pressure gets low
The engine starts overheating
Something triggers the security alarm

You can extend the running time to 30 minutes by repeating the request procedure above with the engine already running on the first request.

Remember, you only get a maximum of 30 minutes, combined or separate, of a remote start. You have to start the truck normally to refresh.

How to Remote Stop a GMC Sierra

If you want your truck off before the allocated 15 minutes or extended 30 minutes, you can still initiate an on-demand shutdown.

Tap the Power Button (that now displays a countdown) to stop the engine on the app.
With a key fob, press and hold the remote start button for 3 seconds to stop the engine.

Why is Remote Start Not Working on My GMC Sierra?

A couple of things could keep your engine from remote starting. Most of them are safety lockouts and won’t need a mechanic to fix them. Here are the most common problems

A partially open or fully open hood
One or more doors are open or not firmly closed
The key fob is in the vehicle
The hazard lights are on
You have already exhausted the two remote start provisions and have to start the engine manually to reset
The transmission is not in Park position
Your start battery is low
The Check Engine light is on
Your key fob battery is low, or you are too far away from the car
Your smartphone has no internet connection
The remote start system is malfunctioning

How to Reset the Tire Pressure Sensor on a GMC Sierra

Your tire pressure monitoring system (TPMS) keeps track of how much air is in your tires. If things fall below or rise above spec, the TIRE PRESSURE warning light will flash on the dash.

Should the light pop up in your GMC Sierra, your first step should be inflating your tires.

Inflate your tires to recommended pressure. You can find this on the driver’s door sill or in your owner’s manual
Drive your vehicle on the highway at around 50 MPH for over 15 minutes to acclimatize the TPMS sensors to the new pressure

If everything goes right, the TPMS light should go away on its own next time you start the truck. If this doesn’t happen, follow this reset procedure.

Turn the truck to the ON position but don’t crank the engine
Locate the TPMS reset button (location varies. 2017 model has it to the right of the steering wheel)
Press and hold until the TIRE PRESSURE light blinks thrice
Start the truck and wait for 20 minutes for the light to reset

An alternative but radical solution could be cycling the tire pressure. The drastic high and low-pressure readings could jolt the sensor and system, forcing it to reset.

inflate the tires to 2 PSI above the recommended pressure
Deflate the tires fully
Inflate the tires to recommended pressure
Drive around for around 15 minutes
Stop and start the car to see if the light goes away.

If you still have the warning light after these attempts and are confident your tires are at the correct pressure, you could be dealing with a faulty sensor.

A good scan tool could check the TPMS system and pinpoint which sensor caused the problem. Some things that could cause problems to include:

Low Battery on the TPMS Sensor

TPMS sensors in the wheel run on a battery to transmit data to the central information module. While they are low-power units that last for up to five years, the battery will eventually run out after years of use.

If this happens, you will get a warning on the dash. Luckily, this should be around the time when you change your tires. Consider replacing your TPMS sensors when replacing your tires.

Too High or Too Low Temperatures

GMC Sierra TPMS sensors work best between -10 and 70 degrees celsius. Anything out of this range could mess up with the system.

If you live in a freezing place, your TPMS might give warning lights after frigid nights out on the driveway.

Aerosol Tire Fillers and Treatments

Sometimes, you might opt for aerosol tire fillers and other liquid treatments to plug slow punctures or rim leaks for a while.

Even though this will keep the air in, it could corrode the TPMS sensor ruining the battery and the unit itself.

Note: Like most sensors, GMC Sierra TPMS sensors are at their most active when the car is on, and you are driving. Expect a slightly longer lifespan if you do not drive around a lot.

How to Reset Service Airbag Light on GMC Sierra

Airbags are one of the best passenger protection features in modern vehicles. They are part of the supplement restraint system (SRS) that creates a softer cushion to protect you from hard impacts after a collision.

As such, GM has a couple of error reporting routines that pop up the airbag or SRS light as soon as they detect a problem in the airbag system.

Only Reset after Servicing the System

Since airbags are so important, you should keep on driving with the light on or suppress it without making repairs. It’s not only risky for the car occupants but might void your insurance in case of an accident.

Get a good OBDII scan tool to pull up the errors related to the airbag system. This will direct you to the actual problem that triggered the light in the first place.

Once the problem is fixed, chances are your service airbag light will go away next time you start the car. The airbag is part of the vehicle’s pre-check on startup. That is why it lights up for a few seconds and goes away after starting a car that’s in working condition.

Even though the scan tool can reset it, you don’t have to. If the repairs were spot-on, the light would disappear the next time you start your vehicle.

How to Clear the Service Airbag Light

Here are the steps to take when clearing the airbag light

Ensure the vehicle is in park or in first gear in a manual transmission and apply the handbrake
Turn the vehicle to ON but don’t crank the engine
Plug the scan tool into the OBDII scan port
Once the scan tool connects to the ECU, navigate to ‘Body Control Module.’
Select ‘Codes’ the ‘Clear All Codes’

If there are no more problems with the SRS and airbags system, the light will stay off next time you start the engine. If you cleared the codes without servicing the system, it would pop back up.

Here is a look at some of the things that could trigger the Service Airbag warning light in any vehicle.

How to Unlock a GMC Sierra Without Keys

If you have your keys locked in the car or you’ve left them somewhere you can’t go, some skills on how to open the truck without the key will come in handy.

Getting an auto locksmith to handle the ‘breaking is the safest and easiest way to gain access to your truck. They will do it fast and with minimal damage to your vehicle compared to what you can do.

ProTip: Don’t try opening a truck that doesn’t belong to you without explicit written consent. This could amount to vandalism or grand theft auto. Even if you are helping a friend or spouse, get permission in writing or even video if things go south and demand you fix any damages.

Even with consent, some of the tools locksmiths use to open locked-out cars can be illegal to own or fabricate if you don’t have the proper licenses.

We will touch on straightforward backup opening techniques and leave the rest to hiring a professional locksmith to avoid the legal complexities.

Always Have Spare Keys

A spare key is a great way to get into your GMC Sierra if you locked your keys in or lost your primary fob.

All you have to do is make a quick dash to where you store the spare key and come back to recover your truck without any damages.

Use the myGMC App

The myGMC lets you control multiple vehicle features, unlock it, remote start, and more without using the actual keyfob.

Note that the app will only work if your vehicle has automatic locks.

It doesn’t matter whether you install the app before or after locking your keys in the car. It can still bail you out as long as the vehicle is legally registered to you.

ProTip: If you already have the app, skip the download and registration steps below and go straight to unlocking the doors

Download the myGMC app from the Apple App Store or Google Play Store
Create an account or log into your GM account if you already have one
Ensure you use the GM account email you provided to the dealer when purchasing the car
OnStar has free and paid features. The free version should let you unlock the doors
Once logged in to the App, add your vehicle to the App using its VIN
If the car belongs to you and the information matches, it will be added
If you have any problems logging in, you can call OnStar for assistance
Once you successfully add the car, you can pull up the ‘Unlock’ command to open your truck using your smartphone

You need an active data connection on your smartphone and be in a place with cell coverage since the truck needs cell coverage to receive the unlock instructions from the OnStar servers.

As of now, GMC uses Verizon Wireless, and AT&T carries in the US. China uses China Telecom.

What Can You Do with the myGMC App?

The myGMC app can do a lot on a GMC vehicle manufactured from 2010 onwards. That’s why dealers insist on registering you at GMC Owner Center, making things easier to log in once you leave the dealership.

If you are buying a used GMC truck manufactured after 2010, ensure that you liaise with the seller to transfer the vehicle ownership to you on OnStar.

This gives you peace of mind because the seller can no longer access your vehicle and gives you the freedom to use the app and OnStar services to the fullest.

Once connected, you can use the app to:

Disclaimer: All these might not apply to your GMC Sierra. They’re applicable in the right vehicle trim and model year.

Command Category	Command
Remote Commands*	Start/Stop engine Lock/unlock doors Honk horn and flash lights
Vehicle Status	Show fuel efficiency and range Tire pressure Display oil life status Show odometer reding Show charge status in EV Show Diesel Exhaust Fluid if equipped
4G LTE WiFi Hotspot (if equipped)	Purchase data Change hotspot password and name
Navigation	Get your vehicle’s location on a map Send nav directions turn by turn or to the infotainment of your vehicle
Vehicle Locate	See your vehicle’s location on a map Geofence your vehicle and get notifications to specified contacts when it leaves or approaches the geofence Set vehicle notification preferences
Preferred Dealer	Search for a dealer or set a favorite dealer Schedule service Check for recalls
Assistance	Contact OnStar Support, Roadside Assistance or GMC Support
Vehicle Service	View required maintenance schedule Schedule or edit service appointment with a participating dealer Recieve updates from dealer when vehicle received and serviced by participating dealer See service recommendations Get alerts for urgent recommendations, low engine oil, or recalls

Aftermarket Door Unlock System

While aftermarket alarm systems are losing market since manufacturers are making stock security harder to beat, you can still use an aftermarket system to reduce the chances of being locked out.

Since alarm systems give you a fob that can unlock or lock the doors as it arms and disarms an alarm, you could use a similar system to provide you with a secondary spare that only unlocks the doors.

You can then hide the fob somewhere under your car. A magnetic or welded box could be a good hide box.

This gives you a way to access the car when locked out. It also gives you peace of mind since, unlike a complete spare key, someone can’t drive off with your vehicle in case they stumble upon the spare door unlock fob.

Takeaways: Lockouts can happen to even the most careful car owners. Apart from actively keeping the key on you when stepping out, you can avoid the problem by setting up a backup keyfob or setting up myGMC in advance.

How to Program GMC Sierra Garage Door Opener

A garage door opening system built into your car can be highly convenient. You no longer have to fumble for an opener fob every time you pull up your driveway. It will be right there, built into the headliner next to your dome lights.

GM uses HomeLink to connect to your garage door opener. You should have some buttons for your Universal Home Remote system in the truck. While the actual programming might vary from one model year to another, the general programming procedure is here.

You will need your garage door opener remote to affect the programming.

Press and hold onto the two outside buttons until the light indicator flashes next to the middle button. ( Could take up to 20 seconds before it starts flashing)
Hold your garage door opener remote about 2 inches from the Universal Home Remote button in the truck.
On the opener and the truck buttons, press and hold the button you want to program onto your GMC and wait until the indicator lights on the truck’s system flash rapidly to indicate successful programming.
To confirm the learning, press and hold the newly trained button on your GMC Universal Home Remote buttons deck and observe what the status light does.
The indicator light should stay on for as long as you hold onto the button if the programming is successful.
If it blinks rapidly then turns to constant light, you have additional programming to get it working.
Go to your garage door opener receiver or motorhead unit and locate your learn/smart button. The location could vary from one garage door opener model to another.
Press the button firmly and release it to enter learning mode
Return to your vehicle within 30 seconds and press the button you previously programmed for 2 seconds, then release

This should program your new button to the garage door opener. If it doesn’t, consider trying the garage door opener button again with someone in the car to press the correct button as soon as you initiate the learning sequence.

ProTip: This is a general guide, and the actual steps might vary from one garage door opener model to another. Consult your garage door opener’s user manual to get exact directions on how to program a universal controller to the system if the above steps fail.

Once you’ve programmed your GMC Sierra to open your garage door, you should remember that it is now essentially a big key to your home.

Take extra precautions to ensure that it doesn’t land in unauthorized hands as someone could use it to gain access to your home.

Keep your truck locked at all times.
Always pack the truck in the garage and not on the driveway
If the car is stolen, reprogram your garage door opener to prevent the truck from opening the garage
Install a robust lockable door from the garage to the house to ensure anyone who gains access to the garage can’t enter the house without a second key to operate the door

How Much Weight Can You Put in the Bed of a GMC Sierra 1500

Depending on the trim, your GMC Sierra 1500 can haul between 1730 and 2430 pounds on a bed between 69.6 and 98.4 inches long to about 80 inches wide.

GMC uses 1500, 2500, and 3500 naming in their trucks. This is similar to what Chevy and RAM use in their trucks.

Class	Meaning	Capabilities
1500	Half (1/2) ton truck	– Old half tons could haul up to 1000 pounds – Modern ones can haul up to 3000 pounds in the bed – Can tow between 9000 and 10000 tons depending on powertrain
2500	Three Quater (3/4) ton truck	Old models could haul up to 1500 pounds on the bed Modern units can carry up to 4000 pounds and tow up to 14000 pounds
3500	1 ton truck	Old models could carry 2000 pounds Modern units can carry up to 6000 Can tow up to 36,000 with the right powertrain

What Happens if I Exceed My GMC Sierra’s Payload Capacity?

Exceeding your load capacity is dangerous in a couple of ways. It overloads your truck’s suspension making the vehicle handle worse. This could make it harder to steer.

Additionally, the extra strain on the suspension will lead to faster tear and wear and could even render your rig unroadworthy.

The engine will also be under stress. You could quickly overheat going uphill, and your truck will be sluggish even on straight lines. Your braking system will also be overloaded, and your stopping distance will be heavily overmatched.

How Much Can the GMC Sierra 1500 Tow?

Like any truck, the towing capacity varies depending on the model year, engine, and transmission. This comprehensive GMC Sierra trailering PDF should give you a detailed breakdown of your truck’s towing capabilities.

The PDF has a breakdown of the complete GMC truck range. Consider bookmarking the page or downloading it for future reference.

We will briefly break down some of the truck’s configurations and towing capabilities.

2022 GMC Sierra 1500 Towing Capabilities

Engine	Transmission	Notes	Max Conventional Hitch
5.3L EcoTec 3 V8	8 speed	Regular 4WD Long Bed	9600 lb
5.3L EcoTec 3 V8	8 speed	Double cab 4WD Max trailering PKG	11200 lb
2.7L Turbo		Crew 4WD Standard bed	8800 lb
6.2L EcoTec 3 V8		Crew 4WD Short bed Max trailering PKG 18” wheels	11700 lb
Duramax 3.0L Turbo Diesel I-6		Double cab 2WD Standard bed size	9300 lb

What Does the GMC Max Trailering Package Entail?

The max trailering package brings additional tuning to your Sierra, making it better at towing. Trailering package models had a higher towing capacity if you are keen on the short, non-exhaustive list above.

Some of the additionals you get with the max trailering package include:

Suspension tuned for trailer towing
An enhanced radiator for better cooling
An automatic locking rear differential
Heavy-duty rear springs
9.76” rear axle for better resilience
A 220 amp alternator to make powering the trailer easier
3.42 axle ratio
An integrated Trailer Brake Controller

How to Reset Change Oil Light on a GMC Sierra

GMC Sierra trucks can track your oil life and tell you when it is almost time to go for an oil change.

Mostly, the change engine oil will pop up when you’ve covered the recommended mileage after your last oil change. It will also gradually track remaining time in a handy 0 to 100 oil life grade.

ProTip: If you had your oil changed at an authorized dealer, chances are they reset the tracker. It is time to take your truck for service if it pops up.

Confirm When You Last Serviced the Truck

When the light pops up, check your service records and check when you last serviced your truck and got an oil change. Chances are:

The car is due for an oil change
The oil life tracker wasn’t reset last time you changed the oil

Whatever you do, ensure that you don’t just shut off the warning light without changing the oil if necessary.

The procedure to reset the light varies depending on whether your vehicle has the Vehicle Information Center (VIC) system. 2006 and later models have the system, and the reset procedure is different from pre-VIC trucks.

How to Reset Change Oil Light in Pre 2006 Models Without VIC

Get into the truck and sit on the driver’s seat
Close all the doors firmly
Insert your key into the ignition and turn it to Accessory power
All lights, including the Oil light, will light up
Press the accelerator to the floor fully three times within five seconds of this.
The oil light will flash the turnoff.
If it doesn’t, perhaps you didn’t do the three accelerator depressions right within 5 seconds. Repeat the procedure again

Resetting Change Oil Light in a 2006 or Later GMC

Get into the driver’s seat and close the door.
Turn the key to accessory power position (or press the start button with your foot off the brake pedal)
With the oil life message displayed, press and hold the Enter button on the Driver Information system for a second
The Information Center will show an acknowledgment message.

Turn the key to the off position before turning on the truck. The oil Maintainance light won’t show up until the recommended mileage has gone by and it’s time to change your oil again.

How to Install the Front and Rear License Plate on a 2020 GMC Sierra

Some states in the US don’t mandate a front license plate. As such, some vehicle manufacturers skip installing an elaborate front license plate well and just give you a rear slot.

GMC Sierra seems to have taken on this trend with the 2020 model. You have to drill into the bumper if you want a front license plate.

Installing the rear plate is a bit easier since GMC left a flat slot at the center of the rear bumper that is perfect for a license place.

Get a License Plate Adaptor

The best way to install a front or rear license plate with minimal damage to your truck is by installing a license plate mount bracket first.

This gives you the freedom to drill or screw in the adaptor once and then install multiple plates onto your truck without tampering with the bumpers anymore.

There’s a wide range of adaptors going for different looks. For the front, look for an adaptor like this that can go through an opening in the front bumper and screw into hardware behind, as this will negate the need to puncture the bumper.

You can get other adaptor options here on Amazon.

Follow the instructions specific to the adapter. You get to properly mount it to the car before screwing or bolting the license plates onto the adapter.

What Do States With Front Plate Laws Require

Since we can’t cover the laws in all states, we will look at standard rules that apply to countries and states that mandate a front license plate.

Must be clearly visible
Securely fastened and does not swing around.
Mounted reading from left to right, and the right side up
Not more than 60 inches above the ground
With the original reflective coating still intact

The rules could limit cheesy workarounds like placing the license plate on your dashboard. Though still visible, it is at the wrong spot.

Can I Use Magnetic or Adhesive Plate Mounts?

Magnetic mounts are a great way to mount plates onto metal surfaces momentarily. However, with the advent of crumple zones and plastic bumpers, you won’t find much or any metal at the front or rear of your truck.

Adhesive plate mounts could be a workaround to stick the plate to flat surfaces on the bumper. While they might work for a while, the adhesive is bound to come loose, and you’ll be left with a big smear or even damaged paint.

These solutions aren’t as long-lasting as bolting, and you could end up losing your number plate on the highway, which is honestly a bit of a hazard.

Why Are Front Plates So Important in Some Regions?

Front plates are mandated in some places since they make it easier for people and law enforcement to identify a car. You don’t have to wait until the car drives past to observe the rear place.

Moreover, they give AI and camera equipment better data to compare the front and rear plate photos to ensure it reads the correct information.

Some automated garages and parking spots use the front plate to process your parking ticket and open barriers; hence having one will be extra convenient.

Yes, they might look bad. But having them on your GMC Sierra truck could make life easier, especially if you frequently trek across states and countries.

What is the Elevation Package on a GMC Sierra?

The Elevation package is a trim on the Sierra 1500 double cab that adds some style and looks to your truck to give it a different stance. Apart from the elevation badge, you get extras like:

Body-color grille, moldings, and door handles
Upgraded audio system
Body-color bumpers

Other extras vary depending on the year model. Consult with the GMC configurator to determine what the Elevation package offers in the GMC Sierra you are eyeing.

How to Turn Off Auto Stop On GMC Sierra

The auto stop is a recent feature in many vehicles that shuts off the engine when the car idles for a while.

Some GMC Sierras have the Start/Stop technology and shut down the engine when your vehicle comes to a complete stop. The tachometer goes to the ‘auto stop’ zone, and the engine goes silent.

This feature does away with short idling times that add up significantly in traffic jams full of start and go traffic.

The engine will start again when you take your foot off the brake pedal in preparation to pull away. The engine could also start if it needs to run air conditioning or pump extra juice to keep electronics running.

There is an Off button on the panel under the climate control to the left of the hazard light that turns it off.

The catch is you have to press it every time you turn on the car as the Sierra will default to auto start/stop on for maximum fuel savings.

Is There a Way to Permanently Disable Auto Start-Stop?

Some aftermarket mods simulate the button press every time you start the car. The device installs between the factory harness and the control panel bearing the start/stop button.

While it involves no programming and has no known impact on the car’s performance, it is a bit involving as you have to pull apart the dash’s infotainment and climate control section.

If you have ever upgraded your audio stereo, this should be easy. Otherwise, look for someone experienced to help you handle it.

ProTip: We don’t recommend such modifications unless your kit lets you use the button to turn on or off the feature permanently. Auto start-stop is an excellent way to save fuel and reduce emissions.

GMC Extended Parking Auto Stop

GMC has a version of the feature dubbed Extended Parking that shuts off the engine when you park your vehicle for a while to reduce emissions and lower fuel consumption.

Extended parking will automatically turn off the vehicle after 20 minutes if parked and the key fob is not in the car. It will take an hour of idling before shutting down if the fob is in the car.

You can disable this feature by pressing and holding the Start Button until the driver information center shows the message “Automatic Shutdown Off.” The feature will reset the next time you turn on the truck.

Why Do People Hate Start Stop So Much

Auto start-stop introduces a minimal lag between releasing the brake and the car crawling ahead. This slight delay can be a bit jarring when driving such a vehicle for the first time.

You have to get off the brake fully let the engine start before using the brake again to creep forward again. It can even be more jarring if you drive a manual transmission vehicle without stall protection.

However, if you tune your mind to it, you will soon be reaping the vehicle’s fuel-saving feature, especially if you often drive in traffic jams.

Finally, the start/stop system can be quite tasking to your starter battery. You will get warning lights if you leave the truck parked for long or don’t drive long enough in the open roads to get the battery fully charged.

How to Program a GMC Sierra Key Fob

Programming a spare GMC Sierra key fob is simple as long as you have a programmed ignition key with you (the key you use to open and start the truck).

If you lost all keys and didn’t have a spare, you will need help from the dealership or a credited locksmith with the right equipment to program a new key.

Programming a GMC Sierra With A Cut Key

Open the GM Sierra using your working remote fob and close all the doors
Pop out the physical key and insert it into the ignition. Then with the other hand, press and hold the ‘Unlock’ side on the central lock button on the driver’s door
While still holding the lock button, Turn the key in the ignition to ‘On’ then back to ‘Off’ twice quickly
Release the ‘Unlock’ button on the door and wait for the car locks to cycle. This indicates that the programming sequence has been initiated
On the fob, press and hold the ‘Lock’ and ‘Unlock’ until the doors respond by cycling locking again
Turn the key in the ignition back to the ‘ON’ position to end the learning cycle

Programming a GMC Sierra With Push Start Button

If your GMC Sierra has a push-button start, it has an intelligent key, and you can’t use the above procedure to program the spare. Here is what will work for you:

Before starting, you will need a locksmith to cut the physical key hidden in the smart key such that its grooves are a perfect match for the cylinder lock on your door.

Get something to time yourself as GMC sets timers for each precise action. This might extrapolate the running cycle, but it is harder for another person to program a key fast into your truck.

Insert the cut key into the lock barrel with the driver-side door open and turn it counterclockwise five times.
You will see a ‘Remote Learning Pending’ on the dashboard. Start your timer and wait for 10 minutes.
Close and open the driver-side door if the dash is no longer lit by the tenth minute.
The dash will light again, and you will get a ‘Press Engine Start Button to Learn.’
Press the Start button and reset your timer for another 10 minutes
After the 10 minutes, repeat steps 3 to 5 again
After the third ten minute mark, close the door and open it again to light up the dash.
You will see the press engine start button to learn again
Press the start button. This time, you will get the message ‘Ready for Remote 1.’
Put the transmitter fob of the smart key into the Transmitter pocker. It is either in the center console cubby or next to the cupholders depending on your model (refer to image under these instructions)
Ensure the buttons on the fob are facing the rear of the vehicle
Press the start-stop button again
Remove the transmitter from the pocket and press either the lock or unlock button.
Press and hold down the Start/Stop button for 12 seconds to exit programming mode.
After this, try starting your vehicle and see if it’s fully programmed. If you followed the instructions to the latter, it should start your car no problem.

How to Use the MultiPro GMC Sierra Tailgate

There’s more to the 2020 GMC Sierra truck than just locking and unlocking it. Dubbed the MultiPro tailgate, it has multiple positions and features that will come in handy when out in the field.

What is the Sierra MultiPro?

The MultiPro tailgate is a two in one assembly. There’s the traditional primary gate and another smaller gate nested in it. The smaller one hinges on the main gate. The two combine in different ways to achieve various functions.

Does My Truck Have the MultiPro?

The MultiPro tailgate is equipped in the 2020 GMC Sierra and the Sierra Heavy Duty. From 2021, it is standard on:

Base Sierra 1500 trim
Sierra 1500 Elevation, SLE, SLT, Denali, and AT4 trim
Sierra Heavy Duty

What to Do With the GMC Sierra MultiPro

Here is a look at the different things you can do with the GMC Sierra tailgate. It ranges from simply unlocking or locking the tailgate to altering configurations for better usability.

Open and Locking the Primary Gate

The first and primary use case is opening the entire main gate. You can do this by pressing the open button on the tailgate, the remote key fob, or the instrument panel.

There’s a torsion spring and damper to make the opening and closing smoother hence your tailgate won’t bang at the bottom.

Lifting the Secondary to Create a Loadstop

If you are lugging around long items like drywall sheets, you can unlatch the inner gate and lift it perpendicular to the main tailgate. This will give you a longer bed by using a section of the tailgate as the bed, and a short load stops to prevent your plywood or drywall from sliding out.

Full-Width Step

Climbing into a truck bed can be quite tasking. If you are tired or just not as agile, the MultiPro lets you unlatch the inner gate and use it as an extra step that can support up to 375 pounds.

Unlatch and lower the main gate before opening the inner gate to use this step. By deploying the hand grab store in the cargo box, you can make things easier.

Easy Truck Bed Access

With the main tailgate open, you have to lean over quite the distance to access the truck’s bed floor. You can get closer by lowering the inner gate with the primary gate open. Stepping into the space, it creates brings you up to 9 inches closer to the pickup box floor.

Comfortable Height Work Surface (Workbench)

Leave the main tailgate closed and only open the inner gate. As it latches open, you will remain with a small working table at a comfortable height than what the main tailgate will give you.

Inner Tailgate Loadstop for Tiered Storage

The MultiPro has another load stop that could let you divide the cargo be into two. One lower section for shorter loads and an upper section for longer things.

Leave the main tailgate closed and lower the inner tailgate as you would when creating the workbench above. After this, lift the inside panel of the inner gate panel to create the vertical load stop.

You will now have a tiered load compartment with the upper section allowing you to load longer but less wide things on your truck bed.

What Does the Service StabiliTrak Warning Mean?

GMC Sierra trucks (and newer GM vehicles) come with an advanced traction control system called Service StabiliTrak that’s in charge of controlling slides.

StabiliTrak gives you better control of your truck on a wide range of surfaces, making it easier to control your GM. If the warning pops up, something is wrong with your truck, and you will no longer have traction control assistance.

How Does StabiliTrak Work?

The StabiliTrak system uses a system of sensors and modules to establish if the vehicle responds to all your inputs accordingly.

If the system detects that you are not getting as much reaction from your inputs, the Sierra could use brakes on specific tires or reduce engine power to help you retain control.

For instance, damping the throttle and braking one rear wheel could help point the vehicle in the direction you are steering towards in case the front wheels lose traction on ice.

Signs That Your StabiliTrack Has Problems

You won’t really notice any changes in your driving if StabiliTrak is off – unless you are in a tricky situation. By then, it might be too late, and you won’t have the attention you so much need to stay on the road.

Some of the signs you shouldn’t ignore to ensure your StabiliTrak is online at all times include:

The Service StabiliTrak Warning Light Comes On

The most significant warning is the Service StabiliTrak light. While your truck will keep driving, and you might be tempted to ignore the warning, getting a certified mechanic or the GM dealership to scan your GMC is the best way to handle the problem.

Cruise Control is Off

Your GMC Sierra relies on StabiliTrak to remain in control when on cruise control. If there’s a problem in the system, you will no longer have cruise control.

Traction Control is Not Working

GMC Sierra also has traction control on top of StabiliTrak. Traction Control is in charge of keeping wheels gripping and reducing unnecessary spinning. Since it uses the same sensors that StabiliTrak relies on upon, it might not work if you have faults in your StabiliTrak system.

Why is My GMC Sierra Displaying the Service StabiliTrak Light?

A couple of things could mess up your StabiliTrak triggering the Service StabiliTrak light. Since it is a complex system, more than the common could cause problems.

Looking at the following obvious problems is a great way to troubleshoot at home. If the system still shows errors, a GM dealer or certified service shop will be your only way out.

You are Running the Wrong Tire Size

Using the wrong size of tires will throw off your wheel speed sensors. The sensors will no longer tell if your wheels are slipping or spinning right.

Stick to recommended tire sizes to avoid such problems. If you want to change the wheel size, ensure you change both the rims and tires to maintain the sweet-spot wheel diameter.

The Brake Pedal Switch is Faulty

Apart from turning on your brake lights, the brake pedal switch also serves as a StabiliTrak and cruise control sensor. If it is faulty, the system won’t have all the necessary information to run and throw the error.

You could confirm if the switch is working by checking if the brake lights come on when you place your foot on the brake pedal.

Faulty Wheel Speed Sensors

Wheel speed sensors are another part of the StabiliTrak system that monitors how fast wheels are turning. The system can use this information to determine whether you are sliding or slipping.

ProTip: The sensors sit in the wheel wells. If they are caked with mud or snow and ice, chances are they won’t work. A fix could be as easy as cleaning your wheels and the wheel wells.

One or more faulty tires starves the system of crucial data making it default to off instead of guessing and potentially offering harmful corrections.

After checking these simple things out, if you still have error codes, then a dedicated scanner tool to bring out StabiliTrak-specific errors is your only way out. Other things could go wrong between basic sensors, wiring, actuators, and control modules that could trigger the error.

How to Reset Stabilitrak on GMC Sierra

Your GMC Sierra StabiliTrak module does a check every time you start up the engine. This means that it will always throw the error as long as there is a problem in the system.

The only option to getting the warning off is having a technician identify the core problem throwing the system off. Under rare conditions, you might have to reprogram the traction control system.

If you changed your wheels, install stock wheels or stick to recommended GM sets for your vehicle or have a technician reprogram the system to accommodate your new wheels – if they must stay.

Resetting StabiliTrak is simple. Here is how to do it

ProTip: Only attempt the reset after applying a couple of fixes like cleaning sensors, checking the brake light, and installing correct tires before trying.

Turn off the vehicle for at least 15 minutes.
Turn on your truck and take it for a short drive (around five miles)
If everything is right, StabiliTrak will disable the error message after a while

Alternatively, you can use the appropriate scan tool to erase the error and take your truck for the drive.

If the fix works, the error message won’t pop up again.

How to Turn Off StabiliTrak

Since StabiliTrak can control how much power goes to your tires if you start slipping, it could cut off power when you need it the most. For instance, it could cut off power when you are slipping in mud when offroading.

This will be counterproductive since, in such a situation, a bit of power could be all you need to keep momentum and avoid getting stuck.

Here is how to disable it

Identify the Traction control button on your dashboard
Press and hold it for at least 10 seconds. This will shut off the system
Stabilitrak will stay off as long as you are driving under 35 MPH. Driving beyond this speed will automatically turn it on.

How to Check Mileage on a GMC Sierra

For a GMC Sierra with DIC buttons, you will have to press the Trip/Fuel button to scroll through different menus. In these menus, you will find the Odometer. Alternatively, you can press the trip odometer reset stem on the dash to show your odometer.

How to Reset the GMC Sierra Radio

GMC uses a high-tech infotainment system in their Sierra trucks dubber IntelliLink. If you just bought a used GMC or are inheriting one, you will want to clear everything and start afresh.

How to Reset GMC IntelliLink

You will have to turn your GMC Sierra to Accessories position or fully on to turn on the infotainment system and execute the reset.

Go to the GMC IntelliLink Home Screen and tap on ‘Settings.’
Select the ‘Return to Factory Settings’ options
You will have three options. Clear All Private Data, Restore Vehicle Settings, Restore Radio Settings
For our purpose, select Restore Radio Settings
Tap on Continue to effect the reset

According to the reset option you pick, you will lose respective data and any configurations you had in that category. You will have to go through configuration a fresh to set up your vehicle just how you like it.

How to Reset Your GMC IntelliLink Password

The system lets you log into your system at the IntelliLink configurations page. You can manage passwords using the online IntelliGrow platform.

Once you have the correct password, navigate to the IntelliLink configuration page in your GMC Sierra infotainment system.

Go to update Gateway Settings.
Enter new username and password
Tap on RESET and enter the new details again

How to Turn on Heads Up Display on 2020 GMC Sierra

If your truck is equipped with a HUD, you can get a range of information projected into your windshield. The lens sits on the driver’s side of the instrument panel.

The HUD controls are to the right of the steering wheel. Here is what you can do.

To turn off the display, rotate the dimming knob fully anti-clockwise until the display turns off.
To turn it on, turn the knob clockwise until it starts displaying. Keep turning it clockwise to increase brightness.
The HUD only turns on if you have started the engine
Use the Up and Down buttons on the HUD controls to center the image. This will either raise or lower the display location
The page button (between the up and down buttons) changes display formats, and the information you’ll get on your heads up display

ProTip: If you use the inbuilt navigation system on your infotainment system, you can get turn-by-turn driving instructions beamed straight onto your HUD system.

GMC Sierra has an automatic ambient light control on its HUD. It will dim slightly or brighten depending on ambient lighting. For instance, you could notice the HUD light up more when under direct sunlight. It will dim immediately after you turn around.

How Do You Reset the Anti Theft System on a GMC Sierra?

The GMC Sierra has the proprietary General Motors anti-theft system that is good enough to replace the aftermarket alarm system.

It has an audible warning that beeps the horn and flashes headlights for a couple of minutes or until you interrupt it.

Start by disarming the alarm by pressing the ‘Unlock’ button on the keyfob. If you have a key, Use the GM key to open the car and use the key to turn the car ignition ON. Unlocking the door in any other way will not disarm the alarm.
Step out of the car and leave a door open. Press the lock switch inside the vehicle to lock the doors. Ensure that all other doors, apart from the driver’s door, the hood, and the boot are closed
Close the driver’s door and wait for the security light in the car to stop flashing

Alternatively, you could close the driver’s door and press the Lock button on the remote fob. This will also pre-arm the anti-theft system. The system will be fully armed if you don’t hit unlock within 10 seconds.

How Do You Reset the ABS Light on a GMC Sierra?

A bad ABS module or a problem in your braking system could throw an ABS light on the dash. With the error on, you will need a scanner that can read and clear the codes.

Once your scanner reads the error codes, ensure that you apply appropriate repairs. Otherwise, you still won’t have ABS, and the warning light will pop up again.

To reset the ABS light,

On your scanner tool, navigate to the ABS menu
Select clear all codes
Power down the scanner and disconnect it
Turn the vehicle on to confirm that the ABS module light is off
Take your vehicle for a short drive to ascertain that it stays off

Signs that You Have a Faulty ABS Module

The most common signs that you have issues with your ABS module or ABS are:

The ABS Warning light pops up
Your brakes will lock up under heavy braking
Unresponsive brake pedals
You need more effort to depress the pedal

Don’t keep driving normally if your ABS light is on. You should be more careful if the traction control light (TCS) light is on too.

You will not have as much control over the vehicle during hard braking as you are used to. The truck can lock up and spin out of control leading to an accident.

GMC Sierra Instrument Cluster Not Working

Sometimes, your Sierra cluster could turn off or display erratically. With modern instrument clusters getting so complex, such a problem is always best left to the dealer or certified mechanic servicing.

Before taking it in, go through the following checklist to establish that the cause isn’t simple problems that you can fix yourself.

Confirm that your battery is producing enough voltage with the engine off
When the engine is on, confirm that your alternator is not overcharging or producing too much voltage for the system
Confirm that the instrument cluster ground terminal is firmly attached and clean
If you installed any aftermarket electronic modifications, disconnect them and see if it fixes the problem. This could be anything electronic, from as simple as an aftermarket subwoofer to as complex as an alarm system
Confirm that all fuses and relays are OK
If you were in an accident or are recovering from water damage and water spills on the dash or any other spot with electronics, have the electronic and wiring system inspected

If any of the above don’t apply to you or they haven’t fixed the problem, you will need a pro automotive engineer specializing in GMCs to help you scan the vehicle and identify the culprit. Sometimes, it might be as easy as reprogramming the instrument cluster, and you’ll be up and running again.

GMC Sierra Headlights Not Working

If you are concerned about your 2014 or 2015 Sierra headlights being too dim, you can check out this class action lawsuit that complaint about that. Here, we will focus on headlights that don’t work at all.

Three main things could make your headlights fail or stop working altogether.

Try Turning them On Manually

If you always rely on the dusk sensing feature to turn on the lights, consider flicking the controls on the stock to ON position manually and confirm that the lights are working.

Try this especially if you notice that the instrument cluster has not dimmed and the headlights lights on the dashboard are not on.

Perhaps someone accidentally moved the switch to the off position, or the light sensors are faulty. If it works, keep driving and have someone inspect the light sensor to restore dusk sensing functions.

A Blown Bulb

A blown bulb will affect one headlight or one type of beam. While it is very rare, you shouldn’t rule it out completely. Luckily, LED headlights on modern Sierras last longer.

If your GMC Sierra has HID or incandescent headlights, consider the fact that the headlight might have blown, especially in high mileage units.

Problem With the Wiring

Another culprit could be your wiring. This ranges from a loose harness to a blown fuse or a faulty ground.

Use the guide on the fuse box to identify the headlight fuse and relay
Pull out the fuse and confirm that it is not blown. If blown, replace with a correct rating fuse
Test the headlight relay too, and confirm that it clicks when you turn the lights on
Use a tester to confirm if you get a 12v signal at the bulb harness.
Run the above test to any ground on the engine bay. If you can get voltage this way and no voltage on the harness ground and positive terminal, then you have a faulty ground.
If there is no ground on both, then you have another problem with the wiring or the headlights control module.

GMC Sierra Power Folding Mirrors Not Working

If your GMC Sierra has power folding mirrors, they should work seamlessly year in year out. Sometimes, gunk or age might get the unit stuck.

Under such conditions, the power folding mirror will sound like it’s trying to close or open but won’t move fully.

If you experience this, you can spray some silicone lubricant to the joint and move the mirror manually, entirely in and fully out to unstick it.

In cases where you can’t hear any motion as the motor attempts to move the mirror, you could have a damaged motor, faulty body control module, a blown fuse, or faulty wiring at your hands.

While you can manually open or close your power folding mirrors, you shouldn’t make a habit of it. It is extra work and could strain the gears, springs, and motor controlling the mirror.

Auto Folding Mirrors Not Working

If the mirrors fold when you move the fold button to close but don’t automatically open or close when you lock the vehicle or dip to curb mode when you go to reverse, you can reprogram them using the following procedure.

If you used the fold or unfold on-demand feature by pressing the fold button, you must open them again for Auto folding and unfolding to resume working.
If you shut off the feature, you will have to turn it on again through the information display system.

Here is how to do it

Navigate to the Settings mode
Go into the Vehicle settings option
Select Mirrors the Autofold
Select ON if they were in Off

If your mirrors don’t fold after these steps, you will have to consult a technician to help you pinpoint the problem or replace necessary modules and parts.

Why is the Cruise Control on My GMC Sierra Not Working?

Cruise control can be a savior in those long highway trips. You won’t have to keep your feet on the throttle or brake to adjust speed whenever someone merges, or you encounter slow traffic.

However, it has to be working 100% else the car will shut it down. Unlike cars of the past that used electromechanical cruise control to alter throttle position, modern GMC Sierras use an electronic system.

Speed information and front-facing radar feed the ECU, which in turn determines how much throttle to use to maintain a set speed limit and when to brake to avoid hitting the vehicle ahead.

A single failure in the range of sensors and actuators will force cruise control to fail to off safely. Here are some of the things that will shut out cruise control in your GMC truck.

A Bad Fuse

Since the cruise control is electronically controlled, it has a fuse protecting its circuitry. If there is a short circuit or current overload, the fuse will blow, and cruise control will fail.

Check your fusebox and the attached layout sticker to identify the cruise control fuse. If it is blown, replace it and keep monitoring it.

If it blows immediately or within days, there must be a problem in the circuitry. Have an automotive electrician help you troubleshoot and fix it.

A Failed Brake Pedal Switch

All vehicles allow you to disable cruise control by tapping on the brakes or the accelerator pedal. The ECU monitors the signal from the brake pedal switch to detect brake input.

The brake pedal switch also controls your brake lights. That’s why they pop on every time you tap the brakes.

If the switch fails, the ECU could interpret this as engaged brakes; hence it will always turn off the cruise control immediately after turning it on.

Failing Speed Sensors

Besides just feeding your speedometer, your speed sensors also maintain other crucial parts of the drive train and traction control system.

Additionally, speed sensors tell your cruise control how fast the vehicle is going. IT can then compare this to your set speed and modify your speed accordingly.

If the speed sensors fail, you will not only lose your speedometer, but cruise control will definitely be unusable.

Faulty Braking System

The system needs access to the brakes to operate optimally if you have adaptive cruise control. If it detects some fault in the system, for instance, the ABS module or low braking response due to low brake fluid levels or worn out brake pads, chances are the truck will disable cruise control.

Issues With StabiliTrak or the Traction Control System

StabiliTrak and traction control system makes it easier to keep driving in a straight line on tricky surfaces.

GMC cruise control will shut off for safety purposes if there is a problem with either of these systems.

Since you won’t be controlling throttle and brakes, the system needs all traction assistance working optimally to keep you on the road in case you don’t react and take complete control fast enough.

Disabling cruise control and forcing you to remain in control when StabiliTrak and Traction Control System is an excellent way to avoid potential mishaps.

ProTip: You will also not have cruise control if you manually deactivate StabiliTrak or Traction Control.

GMC Sierra Battery Not Charging Message

Your GMC Sierra can monitor power delivery from your charging system (the alternator and voltage regulator) to the battery.

If the system detects a problem in the system, it will throw an error that displays on the battery. Chances are your battery will drain fast as you keep driving as it won’t be charging.

Electronics will finally start failing whenever you are not driving fast enough for the alternator to pick up the slack. Moreover, the car won’t start up again without jumpstarting when you turn it off.

The main problems that could lead to the message include:

A faulty alternator that isn’t providing the correct voltage
A worn-out serpentine belt that isn’t driving the alternator enough (could be squealing too)
A problem with the alternator’s voltage regulator
A worn-out battery that isn’t taking in the charge

You can start by having someone with a battery tester check the capacity of your battery and tell if it is still usable.

Batteries are the easiest to fail and diagnose in the charging system. If it is below the threshold, have it replaced. If it is okay, you can go ahead and troubleshoot the alternator and other parts of the charging system.