HELP NEEDED on an 03 GMC Yukon 1500 XL ABS & Brake lights on

[Kcar75]

Hi, I have a couple of questions after spending 2 days trying to fix and nothing worked NEED HELP.. 03 GMC Yukon 1500 XL, battery died and replaced, after replacement two things happened 1. ABS, brake and traction control lights came on and won't go off. 2. HVAC completely quit .. not blowing air. Here is what I have done so far.

 

ABS/Brake/TC lights - changed all fuses, checked and cleaned all grounds, pulled ABS control module and re-soldered the 6 spots related to ABS, re-installed. Had codes checked ... NO CODES SHOWN and all three lights still on.

 

HVAC - changed out all fuses, replaced blower motor resistor, pulled blower motor and checked it and it works fine. After all of that, still NOTHING makes the heat or air come on.

 

Any Ideas ??? I am needing to get my Texas inspection and they won't do it with brake light on ...

[Swimmer8366]

Check your abs sensors. And check the heating element cluster. Weird this is all happening after battery replacement.

 

Sent from my Z981 using Tapatalk

[Jsdirt]

I'd disconnect, wait a period of time, then reconnect the battery, making sure to do it in one motion, without making little sparks - make the connection swiftly. It's easy to double-tap (or more) the connection as you're trying to get the terminal on there. Make sure the terminal is wide enough to make the connection in one shot, then tighten.

 

Sometimes double-taps will get the computer confused. If the problem showed up after a fresh battery install, then I'd try to recreate another replacement by doing the above.

[Kcar75]

I did take battery terminal off but I actually did double tap it and had some sparks. I will try it again in the morning.

 

It is weird how it all happened at once but I went for an inspection again bc I wasn't having any codes and he checked everything with the HVAC and said its probably the control switch panel, so I will replace that this weekend and see if I get heat )

 

As for the brake lights on, he said that nearly 99% of every chevy/GMC around 125k+ have the ABS control module go out, I am going with the assumption that it's just happenstance that it all went out at the same time.

 

To be honest, my old truck needs a lot of work ... it's all little stuff but adds up the $$ and I don't drive it but once or twice a week ...