How to Bleed ABS Module Without Scan Tool

Auto manufacturers equip vehicles with safety features to keep drivers and other road users safe. One of these safety features is the anti-lock braking system (ABS). The Anti Lock Braking System regulates your car in heavy braking situations.

Any time you do any brake system maintenance or repair, such as replacing calipers, master cylinders, wheel pistons, or hoses in your brake system, air can get trapped in the brake circuit. The problem is the trapped air is compressible.

So, whenever you press the brake pedal, the air inside the brake circuit must be compressed before the hydraulic fluid. This will cause a spongy, soft feeling when depressing the brake pedal. Plus, the stopping distance will increase.

You have to bleed the ABS module with a scan tool to remove the trapped air. I understand that not everybody can afford a scan tool. So, in this article, I’ll show you how to bleed ABS without a scan tool and how to know when the ABS needs bleeding.

how to bleed air from abs module

How do I know if my ABS module needs to bleed?

First of all, we have to know the meaning and purpose of an ABS. ABS is the abbreviation of Anti-locking Braking System. This electronic device system processes the signal from the ABS sensors. It then sends this signal to the powertrain control module (PCM). The PCM uses this information to create electronic information that ensures the system works as predefined by the car manufacturer.

In other words, the ABS module is a microprocessor that analyzes data or runs a diagnostic test on the hydraulic braking system and the wheel speed sensors to know when to release braking pressure to any wheel that is about to skid or lock up.

The most common symptom of air in ABS module is a spongy brake pedal. The reason is that the trapped air in the system must be compressed before the pressure applies to the brakes. Bleeding the brake system is all you need to address the underlying issues.

Other symptoms that indicate the ABS needs bleeding include;

  • The illumination of the ABS warning light
  • The appearance of the ESP warning light
  • The ABS may activate even when it is not needed. The brake pedal may suddenly vibrate and jerk.
  • A lousy ABS module or one that needs bleeding will throw error code U0121.

Read Also: Brake Pedal Goes to Floor When Engine Running [Causes and How to Fix]

Can you Bleed an ABS system without a scan tool?

You can bleed your ABS without a scan tool if your vehicle has ABS module bleeder screws.  However, you should bleed the ABS with a scan tool if you need a more straightforward process. You can search for ABS scan tool rentals to rent the tool from your neighborhood.

How to bleed ABS module without scan tool Step By Step

The process of bleeding the ABS module without a scan tool is quite simple. But it might take some time because you need to bleed each wheel separately. So, here you find the steps on How to bleed the ABS module without a scan tool simplified.

Step 1: Park the vehicle

Firstly, park the car on a flat level in a place with good lighting and good ventilation.

Step 2: Lift the vehicle

Block off the wheels with wheel chocks. Lift the vehicle and support the wheels with jack stands. Remove the four wheels to reach the bleeders easily.

Step 3: Drain the brake fluid

With the wheels suspended, locate the brake fluid reservoir in the engine bay. Empty the old hydraulics in it and replace it with recommended brake fluid type. The brake fluid reservoir is typically a transparent plastic container attached to the master cylinder.

Step 4: Bleed the wheels

Locate the bleeding port in the brake caliper and wheel drums and remove the dust cap. Now, slack the bleeder valves and let the brake fluid rush into a container. You can connect a small tube to the bleeder valve and put the other end into the container for easy draining.

Refill the brake fluid and tell a friend or your assistant to pump the brake pedal continuously. The pumping will push out the trapped air in the system along with the brake fluid. Tell the assistant to hold down the pedal while you lock the bleeder valve. Ask him to pump the pedal five to six times and hold it down. Once he’s holding down the pedal, open the bleeder valve and lock it once the fluid stops rushing out.

Remember to keep checking the fluid reservoir every time fluid rushes out of the bleeder valve. Air will get trapped in the system if the fluid in the reservoir runs below the minimum level. Repeat the process on each wheel, starting from the rear wheel on the passenger’s side to the rear wheel on the driver’s side. When you’re done with the rear wheels, move on to the front wheel, starting from the passenger’s side.

Step 5: Check for fluid leaks

Once you are done with the above steps, ask your assistant to depress the pedal continuously so that you can see if there’s a leak on any of the wheels. After that, refill the reservoir with fresh fluid.

Step 6: Test drive the car

Attach the wheels and lower the vehicle. Re-tighten the wheels on the ground and test-run the vehicle to see if the ABS module works as it should.

This is a simplified way of bleeding the ABS module without a scan tool. It’s easy but a little time-consuming.

how to bleed abs module without scan tool

Read Also: No Brake Fluid Coming Out When Bleeding [Causes and Fixes]

How do you bleed the ABS module with the scan tool?

If your ABS module is not equipped with a bleeder, you have to use a scan tool to perform proper bleeding instead of manually activating ABS pump. Using Autel Scanner MaxiCheck Pro will make the job very easy and save much time. But if you can’t afford the tool, you can try one of the cheapest ABS bleed scan tools on Amazon.

Connect a scan tool to the OBD11 port under the steering wheel. It will communicate with the ABS module and activates the pump. Then, follow the prompt to cycle the ABS solenoids to bleed out air.


Can I drive with a bad ABS module?

Yes, you can drive with a bad ABS module. However, the ABS warning light on the dashboard means you should take caution while driving the vehicle.

While you don’t necessarily have to stop the vehicle, some ABS functions will stop working. For instance, the ABS module will not send braking pressure to any wheel about to skid or lock up.

How much does it cost to fix the ABS module?

The cost of fixing a lousy ABS module depends on factors like your vehicle make and model, location, and the technician fixing the vehicle. However, the average cost for ABS module replacement ranges from 340$ to 1,100$. The exact price for your car can be higher or lower than this.

How long should an ABS module last?

The longevity of an ABS module depends on your maintenance culture and driving habits. Under perfect conditions, ABS modules can last as long as ten years or 100,000 miles. But it may fail much earlier if you don’t maintain it properly.

Maintaining proper fluid levels and doing a scheduled brake fluid flush will extend the lifespan of the ABS module.

Is it safe to remove the ABS fuse?

Yes and No. If you remove the ABS fuse, the brakes will still work, but you’ll miss some braking features, such as the ABS module preventing the wheels from skidding or locking up. However, if you need full control of the wheel when racing or want to skid the wheels, removing the ABS fuse is safe.

Can a bad ABS module cause transmission problems?

Yes, the ABS can affect transmission performance. In some vehicles, the transmission control module collects data from the wheel sensors or ABS for optimal performance.

If the ABS module becomes faulty, it will send a false or no reading to the transmission control module. This will invariably cause transmission problems like delayed shifting, hard gear shifting, limp mode, and poor to jerky gear shifts.

Final Words

When you finish bleeding the ABS module and the whole brake circuit, you must ensure everything is in place, and there is no leak. Ask the helper to continuously press the brake pedal to detect if there’s anything wrong.

This is the most simplified guide on how to bleed the ABS module without a scan tool you’ll find anyway. It’s easy and safe. But if you don’t trust your gut or don’t know the working principle of your brake system, contact a professional mechanic.

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Osuagwu Solomon

Osuagwu Solomon is a certified mechanic with over a decade of experience in the mechanic garage, and he has over five years of experience in the writing industry. He started writing automotive articles to share his garage experience with car enthusiasts and armature mechanics. If he is not in the garage fixing challenging mechanical problems, he is writing automotive repair guides, buyer’s guides, and car and tools comparisons.

One thought on “How to Bleed ABS Module Without Scan Tool

  1. HI, Have a vauxhall meriva 2008 1.6 16v car has been off the road for 8months,have overhauld my brakes completely,fitted new brake pipes ,master cylinder ,abs unit,Bleed all brakes no air in system,can not get brake pedal pressure,no trouble codes in ECU ,will pump up at times but will not hold brake pedal pressure,do i need to bleed the ABS system with scan tool ,been in the motor trade ,never come across this,tried everything !

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