A malfunctioning brake module is one of the most difficult issues you can ignore in a vehicle. Yet, the ability to brake can make the difference between life and death. So when your brake module starts malfunctioning, it is crucial to fix it as soon as possible.
Keep reading to learn how to activate an ABS pump and bleed it manually.
Symptoms of air in the ABS module
A bad ABS module will cause your car to lose traction, skid, and hydroplane when braking. As such, it is crucial to know which symptoms you should look out for so you can remedy the issue as soon as possible. Here are common signs of a failing ABS module;
The ABS Light is on
The most common indication of an ABS module issue is the ABS light illuminating. If you have a newer car, it should have an ABS light on the dashboard. If your ABS control module were to go bad, this dashboard light should come on.
It will show an amber color and indicate a problem with the ABS module. Older cars that come with older versions of ABS modules may use a Check Engine Light instead of an ABS Light.
Speedometer Fails
In rare cases where your ABS control module doesn’t work, the speedometer on the dashboard will stop working. Either it will show you an incorrect speed, or the needle will rest at 0 mph.
This will usually be followed by the ABS or check engine light. But even if the light doesn’t come on, a bad speedometer should be enough to get your car checked out by a professional.
The brake pedal is not responding
If you put your foot on the brake pedal and the car does not slow down as it normally does, this is obviously a sign of a problem.
The symptom will start gradually, where you will have to press your foot down on the brake pedal a couple of times to get it to work. But then, as time goes on, you will have to press down more times to perform one braking function.
It may eventually get to the point where it stops working altogether. If you notice issues with the brake pedal, you should also check the brake fluid level and consider having the brake module flushed so you know there is no air in the brake lines.
The brake pad takes more effort to push
If you start to notice that the pedal is taking more effort to get the same amount of braking force, your ABS module might have an issue. For example, you may be in a situation where your vehicle’s brake pedal works, but it requires a lot more pressure to perform a simple braking function.
A brake pedal should not require a significant amount of pressure. You should be able to just lightly press your foot down on the brake pedal for the braking to work. If you have to increase your effort to do this, your ABS control module may be bad.
The brakes are locking up
If one tire is smoking or is constantly locked, you may want to check to ensure you don’t have a stuck caliper. But there are times when a bad ABS module can act erratically, which causes brakes to lock up even under normal driving conditions.
The whole purpose of an ABS control module is to prevent the locking of the wheels. If you notice that your wheels are locking up while you’re driving, then this means that your ABS control module is faulty or damaged.
Some ABS modules may function even if the ABS light is on. You should have the ABS code read, then get the problem diagnosed and repaired. ABS modules have layers of redundancy, and one component or circuit has probably failed.
When should you bleed the brake module?
In normal operation, you do not need to bleed the brake module. But some cases will require bleeding:
The brake pads are completely worn out
Worn out brake pads cause the fluid level in the master cylinder to drop. If it drops too far, the air gets into the brake module.
Disc brake caliper or drum brake cylinder replacement
This requires disconnecting the brake lines. When that happens, air will enter the brake lines.
Replacement of some other brake module components
A disconnected hydraulic part within the brake module causes air to enter the brake lines. Such as the master cylinder.
Compressed caliper piston
Sometimes you need to open the bleeder valve to compress the piston while changing brake pads. This can allow air to enter the brake lines.
How to bleed an ABS module without a scan tool
Bleeding ABS brakes is more challenging than the process of bleeding the brake module. This is because the ABS module has a lot of chambers and moving parts in it. While most ABS modules have bleeding valves, they are not enough to take all the air out. Follow these steps to bleed ABS brakes without a scanner tool.
Items Needed
- Car Jack
- Turkey baster
- Drip pan
- Brake fluid
- Tubing
- Hammer
- Lug wrench
- Car Stands
Steps
- Park the car on a flat level with good lighting and ventilation condition.
- Engage the parking gear to make sure that the emergency brakes are applied.
- Use the car jack to lift the car to a comfortable level to remove the four wheels comfortably.
- Drain the brake fluid.
- Then add new brake fluid specifically manufactured for your baking module.
- If you are unsure of the brand and type, ask your trusted mechanic before buying.
- Then locate the ABS module bleeder screw.
- Locate the bleeding port in the brake caliper.
- Use the correct bleeder wrench to loosen the bleeder screw.
- Next, remove the dust cap, take the vacuum hose tubing, and put one end in an empty plastic bottle and the other end attached to the bleeder screw.
- You will need someone to pump the brake continuously until all the fluid has been drained into the bottle. Which is typically manually bleeding the ABS module.
- Do this on all the wheels and confirm that the brake fluid reservoir is empty.
- Then ask your friend to press the brake pedal down and hold it down.
- Open the bleeder screw to let out trapped air from the ABS module and then tighten the bleeder screw.
- Your friend must keep holding down the brake at this point until you are sure that the bleeder screw is tight as it was before.
- You must repeat this process several times to ensure no air bubbles are left in the brake lines.
- Remember that you have to do this for all the wheels, and it must be in the following order: Right rear, left rear, right front, left front.
- Open the master cylinder and refill with new brake fluid until it reaches the full level.
- Have your friend pump the pedal and hold it down. Then walk around the vehicle to check if there are any leaks because of pumping.
- The braking pedal must go up and down to the recommended levels.
- Lastly, refit all the wheels back.
- You should do a test drive to see if the brakes are working right.
Notes:
- The brake fluid resolve is placed under the hood of your car. It is a small transparent container with metal tubes (brake lines) connecting each wheel.
- Ensure that when you are draining the brake fluid, keep checking the fluid levels on the master cylinder so as not to drain the cylinder and let air get into the module.
- The bleeding process varies depending on the model of the vehicle or the ABS module that you have. However, the steps should help you Bleed most ABS brakes without a scanner tool.
- Check your car’s service manual to know the right way to bleed your car’s ABS since there might be a bleeder bolt on the ABS controller, or you may need to borrow or get an ABS-capable scan tool.
ABS Brakes Won’t Bleed
If your ABS brakes won’t bleed, this is due to improper brake caliper installation. This leads to the wrong positioning of the bleed screw. This results in the bleeding screw being at the bottom instead of the top, which prevents air bleeding since it is lighter than brake fluid and will have risen to the top.
Note: Key takeaway is always to install the right caliper on the right side and vice versa.
Cheapest ABS Bleed Scan Tool
There are several affordable options on Amazon, but they will not be as feature-rich as the costlier options. Below are some cheaper options you can try;