How to Bleed ABS Module without Scan Tool
Modern vehicles have an anti-lock braking system (ABS) that functions by using brake fluid and a pressure system. This fluid may collect some moisture or air bubbles sometimes, which is not good for the braking system. When this happens, you will need to bleed the ABS module to remove the moisture or air pockets. You can do that with or without a scan tool. Here we’ll discuss how to bleed ABS module without scan tool.
What Happens When Air Gets into the ABS System?
Air gets inside the braking system every time you open it for some repairs or other purposes. And some air inside the system affects the brake pedal’s impact, making it feel soft like a sponge upon pressed.
Sometimes, the pedal feels strangely low and sluggish in response when you are pressing it to slow down the car in traffic. It’s a warning sign indicating air bubbles in the brakes. You must remove these unwanted bubbles by bleeding the brakes.
Why does the pedal feel funny when tiny air pockets get into the system? When you apply the brakes, the hydraulic fluid transfer this pressure to other brake components. However, when there is air in the system, pressing on the pedal compresses the air first, making the pedal feels squashy.
How to Bleed ABS Module without Scan Tool
Bleeding the ABS module is time-consuming because you need to bleed at each wheel one by one. Despite the lengthiness, the process is not too complicated for a DIY-er. Follow this step-by-step guide to learn how to bleed air from ABS module.
Things You’ll Need
When you don’t have a scan tool, collect these things to perform the bleeding.
- Fresh brake fluid
- Car jack and jack stands
- Turkey baster
- Drip pan
- Lug wrench
Bleeding ABS Brakes without Scan Tool
For bleeding the brake, you will need to park the car on a flat surface in a well-lighted place. Shift the gear to ‘Parking’ and make sure that the emergency brakes are applied. Doing all these things will prevent the car from rolling toward a direction.
Then, jack up the car and remove all four wheels for easy reaching to the desired areas. You will need to raise the car to a reasonable height for the effortless removal of the wheels. Use jack stands to stabilize the car in that position.
You will need an assistant to help at certain stages. They don’t need to have any experience, just an adult who can follow your commands.
Drain the Brake fluid
Locate the brake fluid reservoir under the hood. This translucent tank has metal tubes (which are brake lines) going in and out of each wheel. Drain the fluid in a drip pan and refill the tank with fresh fluid.
Loosen the Bleeder Bolt and Bleed the Wheel
How to bleed ABS module without scan tool? You will need to loosen the bleeder bolt. Use the correct wrench and don’t remove it completely from the socket. Remove the dust cap and put one end of the tubing to an empty plastic bottle. Connect the other end to the loose bleeder bolt.
Ask your helper to pump the brake pedal until the last drop of the old fluid spurts out and goes into the bottle. When no more fluid is coming out, check whether the reservoir is completely empty.
During this process, the master cylinder cannot be empty. In fact, its fluid level should not drop below the midpoint. Check it constantly and keep adding fluids when it’s about to drop below the half level. Otherwise, air will get into the system and you have to repeat the bleeding process.
Then, tighten the bleeder bolt but ask your assistant to press down the brake pedal and continue pressing until the bolt is tightened properly.
Repeat this bleeding process at other wheels. Start with the right rear one and proceed with the order or left rear, right front, and left front wheel. This bleeding sequence could change depending on the type of ABS system or car model. But this will work for most of them.
Put the Parts back Together
When you’re finished with bleeding ABS brakes without scan tool, make sure that no component in the system has any leak. Ask your helper to pump the pedal while you examine everything to see if there is any dripping. The assistant should be careful to pump the pedal up and down to the recommended levels. Then, refill the master cylinder with fresh fluid to the ‘full’ level. Reattach the wheels and do a test drive to see if the brakes are working right.
So, this is how to bleed ABS module without scan tool. Using a scan tool will make the job easier but if you don’t have one, this way is pretty effective.