GMC Troubleshooting Questions? Ask a Mechanic for Answers
Hi and thanks for the question! This sounds a little complicated. I'll need to ask you come question first. 1. You said this all started at the same time correct? With the 4WD, ABS and red brake warning lights all coming on, it leads me to believe you have an internal issue with the EBCM (electronic brake control module), however, this could also be and input speed issue to the EBCM. The air conditioning isn't tied into this system at all that I can think of, so you may have a couple issues. 2. Can you or have you had anyone pull the DTC's (diagnostic trouble codes). Having that information will certainly help. Let me know
Yes this all started about the same time if not at the same time within a minute or 2 for sure. I had a mechanic check the fuses and while he was there he pulled the codes but there were multiple codes so he wanted me to leave it a day with him.... I don't have another daily driver so I will have to arrange a loaner or rental so I could not leave it and he did not give me a list of codes.. There are some on Google who say possible ignition switch and I have had a issue with getting the key to go in right a bit lately. Others suggest break in a plug in column and to move column up and down while running or key on and I did that with no change. It will be tomorrow before I can get the codes unless these kids go to sleep early and I can get to Auto Zone for a list of codes. Thanks
I see. Yes, the ignition switch is also a possibility. I guess without having some more info on the codes, it's really difficult to say. If you can get those and contact me back, we'll see what we can do for you. Right now, it's just a very broad guess. Let me know what you find out and I'd be happy to help further ok?