2005 Yukon brake bleeding

[imiceman44]

It occurs to me that with a non-clamping brake, the ABS will never need to actuate at that corner. AFAIK, the traction control can apply the brakes (and I activated it several times), but I don't know if that's the same action as cutting brake pressure. This doesn't seem like a control module failure, more like a mechanical issue inside the "pump" section. Even junkyard pulls aren't cheap and that swap means inevitable DOT-3 shower, then hours of bleeding, but that may be where this is headed.

I am guessing those parts are different from my 2003 3/4 ton HD avalanche?
I am parting it in case you can use any of it.
It's a clean California truck

 

[Wes Harden]

since the abs has been activated do another service bleed and test drive. There was air in the abs module, probably water too, now you can get both of those unwanted out of the system.

 

[Blue85]

I am guessing those parts are different from my 2003 3/4 ton HD avalanche?
I am parting it in case you can use any of it.
It's a clean California truck

I don't know if 1500 or 2500 makes any difference, but traction control does. This appears to be the JL4 active brake control. It has 6 lines coming into it, while the more common setup has 5 lines (mine has the rear brakes separate, where the simpler one has a Tee for the rear). I haven't found any evidence the tuning/action is different whether in pickup, Tahoe, Avalanche, etc. I've been using interchange 545-01892, which lists 04-06. My '03 2500 has exactly the same controls, so who knows?

since the abs has been activated do another service bleed and test drive. There was air in the abs module, probably water too, now you can get both of those unwanted out of the system.

I still can't bleed that corner, but I can push fluid up from the back. I was thinking more bleeding is mandatory after my stunt pushing shop air through it.

 

[Blue85]

I took this thing out and rage braked it a few times and then the pedal sank. I knew that was either a good sign or a really bad one. No leaks underneath, I bled some nasty looking fluid out of that corner and then it had good pedal and 4 hot brakes. I think it happened because that morning I ordered another ABS module. While the proportion valve / pressure switch is happy and all 4 brakes are working, there is a permanent DTC for ABS pressure something or other. I can clear it, but the light comes back on in seconds. It's possible that one solenoid went from jammed shut to jammed open. I did haul the trash with it - not having ABS and TC isn't that big of a deal in the summer.