Driver brake drag

[ChevyMan813]

I have a 2005 Tahoe z71 2wd. I’ve checked calipers brake lines wheel sensors and fluids. I am having intermittent break dragging/locking on driver rear after a few miles. I have no ABS or traction light on only service stability on dash. But service stability has been on dash. Ever since truck was hit by lightning almost a year ago. I replaced all modules. They were all programmed besides EBCM but has worked flawlessly until recently. I’m thinking it’s the eBay EBCM. I purchased almost a year ago.

 

[swathdiver]

Need to pull the codes and be able to view data. Who do you know with a Tech-2 or similar bi-directional scan tool?

An IPhone with the CarScanner app from the Apple Store can read all internal codes with an OBDII adapter.

 

[ChevyMan813]

I have a launch elite 2.0 scanner. It’s coming up with codes C0131 for antilock brake system tracking control system pressure circuit malfunction. And code CO292 lost communication with engine system. but I’m sure it had these codes for a while. It just started having dragging left rear brake. I am thinking that EBCM has a malfunctioning valve. or module circuit board is malfunctioning.

 

[blondie70]

You could pull the fuse on the ABS and see if it stops....

 

[ChevyMan813]

Only way brake releases is let it sit off not running for a while or cracking bleeder screw tried pulling fuses didn’t work.

 

[blondie70]

There's a long post on here by a guy with drag problems....he found the ABS pump.valves ??? had a problem and found a solution. But it was a lot of work and he was an engineer...I think. Anyways you could look for that and maybe your problem is the same or similar ??? Good Luck....(I remember that he could pull the fuse and the brakes would release tho...........)

 

[B-train]

Have you checked the rear hose for that caliper? They can check valve themselves with age/damage and hold pressure on the caliper. Bleeding them makes it normal again. Using a line clamp, you could block that wheel off and see how it acts. My guess is there would be no binding.

It's either that circuit in the ABS module that isn't allowing proper bleed back after pressurization or a brake hose collapsing.

One last possibility is a brake caliper hanging up when it gets hot. You could try using a thin block of wood to simulate the rotor and extend the piston out with gradual brake pressure, open the bleeder, and push the piston back. Exercise that caliper a couple times like that to move the seal and get new fluid in there - those aluminum calipers get full of gunk.

 

[ChevyMan813]

Yeah I changed brake line and caliper still dragged so I put factory brake and caliper back on better quality to me I didn’t try changing center rubber brake line but I have it but its intermittent so I don’t think its a line but ‍‍idk

 

[B-train]

Yeah I changed brake line and caliper still dragged so I put factory brake and caliper back on better quality to me I didn’t try changing center rubber brake line but I have it but its intermittent so I don’t think its a line but

Since you did all that with the same results, I'm speculating ABS unit. Do you have the ability to run a bleed cycle on it with a scan tool? Or a gravel road you can do some ABS stops on? You may have a piece of crud floating around by a check valve, etc that needs to get moved on down the line.

 

[ChevyMan813]

My scanner says it does auto bleed but I’m not sure on how to do it I have to read manual.How do I do a brake line test I usually just squeeze and feel around and make sure fluid comes out.