While driving my front brakes apply themselves

Tiny
HAJOK@COMCAST.NET
  • MEMBER
  • 2015 CHEVROLET SILVERADO
  • 5.3L
  • V8
  • 4WD
  • AUTOMATIC
  • 45,000 MILES
I have to bring the truck to a stop. I pump the brakes and they release. I have changed the booster, the air pump to the booster and the cruise and brake module. It still does it. Help
Do you
have the same problem?
Yes
No
Tuesday, February 12th, 2019 AT 3:46 AM

14 Replies

Tiny
JACOBANDNICKOLAS
  • EXPERT
Hi and thanks for using 2CarPros.

Since it is only the front brakes, I question the master cylinder. Try this. When the brakes are locked up, see if they release if you open the brake line at the master cylinder. If it doesn't, work forward. Move to the caliper. Open the bleeder and see if the brake releases.

I have seen situations where the rubber brake hose on the calipers would fail internally causing the brake pads to remain partially actuated or fully. When driving, there would be enough drag on the brakes to cause them to get hot. Now, brake fluid expands when it is hot, so the brakes would slowly continue to engage.

If the brakes release when you open the bleeder on the caliper, replace the rubber brake hose.

Let me know what you find.

Joe
Was this
answer
helpful?
Yes
No
Tuesday, February 12th, 2019 AT 5:46 PM
Tiny
HAJOK@COMCAST.NET
  • MEMBER
I would say it's got to be something in the electronics of the master cylinder is working fine. It's releasing but the traction control light keeps coming on. If you turn it sharp right or left or if the brake locks up. It'll flash on and then flash off, so it's got to be something in the ABS. I just don't know.
Was this
answer
helpful?
Yes
No
Wednesday, February 13th, 2019 AT 12:52 PM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Welcome back:

I didn't realize turning caused this problem. With that in mind, the first thing I would check are the ABS sensors on the front wheels. Check to confirm the wiring isn't damaged, shorted, or not properly plugged in at the connector.

I attached pictures of where the wiring mounts and sensor location. Check both sides. Also, based on the year, I strongly recommend scanning the computer for diagnostic trouble codes.

Let me know what you find.

Joe
Was this
answer
helpful?
Yes
No
Wednesday, February 13th, 2019 AT 7:36 PM
Tiny
HAJOK@COMCAST.NET
  • MEMBER
Turning never caused this problem, it just started when I turn it it acts like it's shaking.
Was this
answer
helpful?
Yes
No
Thursday, February 14th, 2019 AT 4:21 AM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Are you sure the brakes aren't hanging up a bit all the time?
Was this
answer
helpful?
Yes
No
Thursday, February 14th, 2019 AT 6:24 PM
Tiny
HAJOK@COMCAST.NET
  • MEMBER
Yes.
Was this
answer
helpful?
Yes
No
Thursday, February 14th, 2019 AT 7:27 PM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Welcome back:

I forwarded this to the owner for his ideas or suggestions. Expect a response from Ken. I will continue watching what is happening and try to help.

Joe
Was this
answer
helpful?
Yes
No
Friday, February 15th, 2019 AT 2:32 PM
Tiny
KEN
  • ADMIN
Hello,

There are a couple things that come to mind first is the push rod that from the booster needs to be adjusted inward, when the brake are locked loosen the master cylinder mounting bolts if the brakes start rolling you know the push rod is the problem next we should run the codes becasue it sounds like the ABS/traction control module is going out. Lets run the codes to confirm the issue

https://youtu.be/rTtAnsOlZU4

If the module is to blame this video with show you how to replace it with instruction and diagram below to help show you on your truck.

https://youtu.be/lUotkKXG9dY

ABS traction control module replacement reprogramming.

Note:
DO NOT program a control module unless directed to by a service procedure or a service bulletin. If the control module is not properly configured with the correct calibration software, the control module will not control all of the vehicle features properly.
Ensure the programming tool is equipped with the latest software and is securely connected to the data link connector. If there is an interruption during programming, programming failure or control module damage may occur.
Stable battery voltage is critical during programming. Any fluctuation, spiking, over voltage or loss of voltage will interrupt programming. When required install the EL-49642 - SPS Programming Support Tool to maintain system voltage. If not available, connect a fully charged 12?V jumper or booster pack disconnected from the AC voltage supply. DO NOT connect a battery charger.
Turn OFF or disable systems that may put a load on the vehicles battery such as; interior lights, exterior lights (including daytime running lights), HVAC, radio, etc.
During the programming procedure, follow the SPS prompts for the correct ignition switch position.

Clear DTCs after programming is complete. Clearing powertrain DTCs will set the Inspection-Maintenance (I-M) system status indicators to NO.
Reference Information
Special Tools

EL-49642 - SPS Programming Support Tool

Replace and Program Control Module or Reprogram Control Module
To program a replacement or an existing control module, perform the following procedure:

Install EL-49642 - SPS Programming Support Tool .
Access the Service Programming System (SPS) and follow the on-screen instructions.
On the SPS Supported Controllers screen, select K17?Electronic Brake Control Module - Programming and follow the on-screen instructions.
On the SPS Supported Controllers screen, select K17?Electronic Brake Control Module - Configuration and Setup while following the on-screen instructions.
At the end of programming, choose the Clear All DTCs function on the SPS screen.
Unsuccessful Programming Recovery
In the event of an interrupted or unsuccessful programming event, perform the following steps:

Ignition ON. Ensure the control module, DLC and programming tool connections are secure and the SPS software is up to date.
Verify the control module can be reprogrammed.

If the control module cannot be reprogrammed

Ignition OFF for one minute, ignition ON.
Verify the control module can be reprogrammed.

If the control module cannot be reprogrammed, replace the control module.

If the control module can be reprogrammed.

All OK.

If the control module can be reprogrammed

All OK.
Repair Instructions
Perform the Diagnostic Repair Verification after completing the repair.

Control Module References for Control Module replacement, programming and setup

Like JACOBANDNICKOLAS said it could be a bearing hub going out causing the wheel speed sensor to have a false reading.

https://youtu.be/ZgiPRG6jffc

Check out the diagrams (below). Please let us know what you find. We are interested to see what it is.
Was this
answer
helpful?
Yes
No
Friday, February 15th, 2019 AT 6:19 PM
Tiny
HAJOK@COMCAST.NET
  • MEMBER
Found the problem and it was not showing up on the scanner. We've changed the brake booster the air component that went to the booster the brake lines the master cylinder. Could not find anything wrong it was not showing on the scanner the codes weren't there we were changing these parts one at a time and it was still doing the same issues. The first thing we changed was the booster then it showed up it wasn't getting enough air to the booster so we change that component then we change the brake lines then we changed the master cylinder. We were perplexed and could not find the issue we had two other mechanics looking at it. One of them and told us that sometimes the boosters can be bad even though it was from GM and come right out of the box we went back to that we changed and put a new booster on that was the problem. Thank you for everyone helping with this. We just found the problem yesterday we've been two weeks working on this.
Was this
answer
helpful?
Yes
No
Saturday, February 16th, 2019 AT 3:26 AM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Happy to help. What was the actual problem? I'm sure it will help someone in the future.
Was this
answer
helpful?
Yes
No
Saturday, February 16th, 2019 AT 7:53 PM
Tiny
HAJOK@COMCAST.NET
  • MEMBER
We change the brake booster, the pump, the brake lines, and the master cylinder. The new brake booster we put in from GM was bad.
Was this
answer
helpful?
Yes
No
Sunday, February 17th, 2019 AT 2:16 AM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Wow! You buy the best and this happens. However, I guess it can happen.

Regardless, I'm glad it's fixed. Take care and let us know if you have questions in the future.

Joe
Was this
answer
helpful?
Yes
No
Sunday, February 17th, 2019 AT 4:39 PM
Tiny
HAJOK@COMCAST.NET
  • MEMBER
Thank you and everyone else.
Was this
answer
helpful?
Yes
No
Sunday, February 17th, 2019 AT 4:56 PM
Tiny
JACOBANDNICKOLAS
  • EXPERT
Happy to help. And I can't believe I missed your identifying the problem in your prior post. Sorry about that.

Joe
Was this
answer
helpful?
Yes
No
Sunday, February 17th, 2019 AT 5:08 PM

Please login or register to post a reply.

Recommended Guides