This is a 2007 Tahoe with 219K. I have owned it since it had about 80K and it is completely stock (2WD). It had a new transmission put in about two years/20K miles ago. Recently the Stabilitrack/Traction Control lights started coming on. After reading codes, we replaced the throttle body and mass airflow sensor. This didn't help. The lights still came on and would stay on for a while, then randomly go off. A few days later, the brake lights and ABS lights would come on and go off at the exact same time as the Stabilitrack/Traction control. I took it to a mechanic friend and he spent hours and hours pulling codes and running tests and replacing parts and was not able to diagnose the problem. Here is what we have ruled out:
Grounds - he has cleaned and checked every ground
Brake light switch - switch under dash that engages brake light
ABS module and pump - replaced both with a good one - no help
Made sure ALL bulbs are working properly
He drove the car with the diagnostic tool hooked up and says the wheel speed sensors were working fine, but maybe one works some of the time. There is no rhyme or reason to when the lights will come on. They will be off for two days, then come on when the car is started. They will stay on for an hour, or for 3 days, then go off when driving the car, or when you first start it. Sometimes it comes on sitting still, other times when you are accelerating. I have tried to determine if turning the steering wheel effects it, thinking it could be the steering wheel position sensor or a front wheel speed sensor that has some frayed wires that lose connection when turning. But sometimes they come on when driving straight. It runs and drives perfectly. There is no performance problem or any other evidence of a problem. This is my daughter's car and if it weren't for the ABS light being on and the ABS system being disabled as a result, I would just let her keep driving it. But I want to get this fixed without throwing a bunch of random parts and money at it.
From reading through the forums on this topic, the battery may be something to check. It isn't old, but batteries sometimes go bad. It shows no signs of a problem and sounds strong, but you never know. I may swap it with another one to rule that out......
Any other advice would be appreciated! This is a frustrating problem on an otherwise very reliable car.
Grounds - he has cleaned and checked every ground
Brake light switch - switch under dash that engages brake light
ABS module and pump - replaced both with a good one - no help
Made sure ALL bulbs are working properly
He drove the car with the diagnostic tool hooked up and says the wheel speed sensors were working fine, but maybe one works some of the time. There is no rhyme or reason to when the lights will come on. They will be off for two days, then come on when the car is started. They will stay on for an hour, or for 3 days, then go off when driving the car, or when you first start it. Sometimes it comes on sitting still, other times when you are accelerating. I have tried to determine if turning the steering wheel effects it, thinking it could be the steering wheel position sensor or a front wheel speed sensor that has some frayed wires that lose connection when turning. But sometimes they come on when driving straight. It runs and drives perfectly. There is no performance problem or any other evidence of a problem. This is my daughter's car and if it weren't for the ABS light being on and the ABS system being disabled as a result, I would just let her keep driving it. But I want to get this fixed without throwing a bunch of random parts and money at it.
From reading through the forums on this topic, the battery may be something to check. It isn't old, but batteries sometimes go bad. It shows no signs of a problem and sounds strong, but you never know. I may swap it with another one to rule that out......
Any other advice would be appreciated! This is a frustrating problem on an otherwise very reliable car.
