Hello there everyone… I need help finding possible issues… At a loss of what to do, and if this is a major or minor fix I could do myself…
I seem to have a possible major issue with my 2002 GMC Yukon… After starting my truck, I removed my parking brake, and began driving… But a minute or so into driving I noticed my ABS light was stuck lit… I turned off my car and turned it back on, and it remained lit.
The issue is, after fooling around with my parking brake release lever, it seems nothing I did made it turn off. I then noticed a grinding noise from the bottom of my truck, so I turned it off. However, after COMPLETELY turning off my truck and removing my keys from my ignition, it was still making that grinding noise… I parked it while at the grocery store, and got my groceries (30 minutes or so), came out and it was STILL making this noise even while it was powered off which was pretty alarming…
I brought my truck home, and figured its pulling power from my battery, and if I leave my truck alone for the whole night, it will continue to pull power… Sure enough, I disconnected the battery and it stopped completely…
What the heck is going on with my truck? I’m worried to even drive it as I don’t want to get slapped with a nice towing fee and/or get stranded.
Any help would be wonderful and MUCH appreciated…
P.S.: This appears to have happened at the SAME time as the ABS light came on if that helps…
Does this vehicle have the Automatic Level Control system for the rear suspension? Is the noise coming from the rear of the vehicle? If so, the Level Control air compressor could be stuck on, possibly due to a faulty relay or a major air leak. The compressor is located on the rear frame crossmember. You can verify a stuck-on compressor by reconnecting the battery, and, assuming the noise returns, pull the fuse labeled Stud #1 in the underhood fuse block. If the noise goes away, that’s the problem.
If the vehicle also has Stability Control or Traction Control, something wrong with the leveling system may also affect these, triggering the ABS light.
The automatic leveling control makes more of a sound of a small engine. Sort of a put-put sound and it would at the rear. @Bugmenot has the right idea though, pull the fuse.
The ABS is directly under the driver and it shouldn’t be continuously running but it would make more of a grinding type noise. There is also a fuse for the ABS as well. Since you drive it home OK, the base brakes must work. It likely the ABS module or its control has failed.
Either way, you need to get it to a mechanic. If there is a leveling system failure the air-bags around the shock can jam the motion of the suspension causing unwanted nasty handling plus it can do further damage. The ABS should be self explanatory. Brake system problem = service immediately!
Although I couldn’t find anything in the service manual about the ABS pump sticking on, a bit of Googling shows that it is possible, and maybe not that uncommon in these GM trucks, so @Mustangman’s comment on a bad brake module (EBCM) is probably more accurate than my leveling system comment.
Usually a major EBCM fault will also light up the traction and stability control indicators in the instrument cluster, if the vehicle is so equipped.
Sometimes it is possible for a mechanic to temporarily disable the ABS system. If that makes the grinding noise go away, that’s a pretty good clue it is just a confused ABS. Folks here sometimes report ABS noises as a sort of stuttering sound, which they can feel in the brake pedal. Does it seem anything like that? If so, could just be a failed wheel speed sensor or something similar.
ABS systems can sometimes get cranky too. Esp soon after the brake hydraulic system is opened, for example to replace brake pads. Any work like that done recently? I’ve heard of people taking their vehicle out to a gravel parking lot and doing a few brake maneuvers so the wheels lock up a bit, to get the ABS working again when all else fails.