Brake bleeding with ABS?

Good evening.

when the engine is running, is the ABS light still on? You need a scan tool to bleed the brakes. there is no other way to bleed the system. if there is a code set in the ABS, the bleeding procedure will not work. Please check out this guide

https://www.2carpros.com/articles/how-to-bleed-or-flush-a-car-brake-system


Roy

Are you talking about a code reader? i have one of those it reads ABS, engine and airbags.

The tool does reset codes also.

No, they are nothing but code readers. you need a real scan tool that can control functions such as the brake bleeding procedure.

Roy

Oh okay, I will see if i can get one then get back to you. thanks.

Do you recommend a good tool i can buy?

there are many online you can get, but they will be pricey. plan on spending at least $1,000.00 to $1,500.00 for a good quality one.

it would be cheaper to have someone do it for you. it runs around $75.00 at any shop to bleed the ABS.

Roy

Okay thanks. I will tow it somewhere .

Okay, keep us updated.

Roy

Hi Roy sorry its been so long but yes found a guy with the abs tester we bleed the brakes a new experience doing with this tester anyway got the job done ... what a gm screw up...thanks for all your help...
Tony

Your welcome.

Do you have ABS on your truck?

If you do, I attached the automated sequnce for bleeding the brakes.

You will need a scan tool for this procedure.

Roy

ABS Automated Bleed Procedure

Two - Person Procedure

Caution: Refer to Brake Fluid Effects on Paint and Electrical Components Notice in Cautions and Notices.

Caution: Refer to Brake Dust Caution in Cautions and Notices.

Important:
Use the two-person bleed procedure under the following conditions.
Installing a new Electro-Hydraulic Control Unit (EHCU) or new Brake Pressure Modulator Valve (BPMV).
Air is trapped in the valve body.
Do not drive the vehicle until the brake pedal feels firm.
Do not reuse brake fluid that is used during bleeding.
Use the vacuum, the pressure and the gravity bleeding procedures only for base brake bleeding.

1. Raise the vehicle in order to access the system bleed screws.
. Bleed the system at the right rear wheel first.
3. Install a clear hose on the bleed screw.
4. Immerse the opposite end of the hose into a container partially tilled with clean DOT 3 brake fluid.
5. Open the bleed screw 1/2 to 1 full turn.
6. Slowly depress the brake pedal. While the pedal is depressed to its full extent, tighten the bleed screw.
7. Release the brake pedal and wait 10-15 seconds for the master cylinder pistons to return to the home position.
8. Repeat the previous steps for the remaining wheels. The brake fluid which is present at each bleed screw should be clean and free of air.
9. This procedure may use more than a pint of fluid per wheel. Check the master cylinder fluid level every four to six strokes of the brake pedal in order to avoid running the system dry.
10. Press the brake pedal firmly and run the Scan Tool Automated Bleed Procedure. Release the brake pedal between each test.
11. Bleed all four wheels again using Steps 3-9. This will remove the remaining air from the brake system.
12. Evaluate the feel of the brake pedal before attempting to drive the vehicle.
13. Bleed the system as many times as necessary in order to obtain the appropriate feel of the pedal.

I have a '02 Trailblazer in which the brake lines running from the master cylinder to the proportional valve broke and got replace. Now theres very little to no brake fluid running to the the rear wheels and the calipers dont seem to be tightening at all. ive tried bleeding the air out of the lines through the bleed screws but there was no brake fluid coming out. I was told that it may have something to do with a fuse or something. Can someone help me with this?

Unfortunately I suspect we are going to have to just pressure bleed these brakes or use a helper to pump the pedal.

https://youtu.be/w7gUsj2us0U

Sounds like you are trying to bleed them using the gravity bleed method. That works sometimes but we should just us a pressure system or have someone pump the pedal when you are closing the bleeder then hold the pedal when you open it.

Here is another guide that will help with this:

https://www.2carpros.com/articles/how-to-bleed-or-flush-a-car-brake-system

One other thing, when you replaced the line, did you bench bleed the master cylinder again? If not that may be the issue.

https://www.2carpros.com/articles/how-to-replace-a-brake-master-cylinder

So let's run through this type of bleeding and then go from there. Thanks