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2012 Tahoe Service Traction/Service Stabilitrak

Sam 2012 Tahoe

By Sam 2012 Tahoe
in Ask A GM Technician

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Sam 2012 Tahoe Enthusiast

Sam 2012 Tahoe

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while driving on the interstate, I stopped at a rest area and my dash display notified me that Traction was off. Then, it showed Stabilitrak was off. I then got the "Service traction" and "Service Stabilitrak" messages. No performance or other symptoms were noted. I called the dealership from the road, and the service writer suggested shut off the truck and see if it resets. it did, but the Traction stays off. In around town driving, then traction was off, but no more service messages. Then, on the way home, after a few hours of driving (dry conditions), the same scenario repeated. Tire pressure was 35 LF, 36 RF, 36 LR and 36 RR (this is hot pressure). No loss of MPG, or power, handling seemed fine.

 

Any ideas what could be the issue? The truck has 53900 miles.

 

I should also add that when I press the dash button for stabilitrak/traction, and no service messages are being displayed, stabilitrak is "on, and traction is "off". I can set traction back on, but it returns to "off" as soon as the display refreshes. I have tried turning both off and back on again, with no results.

 

1/6 addendum - I have noted that it consistently happens when I make a 90 degree left turn in a parking lot, going in my driveway, etc. but not just changing lanes to the left, or following a left curve. it seems to be only a full left turn, but happens at low speed. It was happening occasionally, but now consistently.

Thanks,

Sam

Sam 2012 Tahoe Enthusiast

Sam 2012 Tahoe

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1/6 addendum - I have noted that it consistently happens when I make a 90 degree left turn in a parking lot, going in my driveway, etc. but not just changing lanes to the left, or following a left curve. it seems to be only a full left turn, but happens at low speed. It was happening occasionally, but now consistently.

Sam 2012 Tahoe Enthusiast

Sam 2012 Tahoe

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1/14 addendum - I have noted a definite correlation between the transmission temperature as reported on the DIC, and the occurrence of this problem. It never happens until the transmission temp is at or over 150 degrees. I have no idea what this nexus means, except that it is consistent. I have traced the right front sensor wire to the wiring harness, and found that it runs under the radiator. Now, could this mean that the transmission fluid (which is cooled at the bottom of the radiator) is heating the wire and causing the fault? The problem is happening much more often now, even slight maneuvers to the left or right, once 150 degree trans temp is reached. This explains why the dealership couldn't duplicate the problem - they let it sit long enough to cool, then only drove it 4 miles, which would not heat the transmission up enough to generate the problem. I'm going to get it good and warm, generate the problem, then take it to them and insist that they come read the codes immediately. I'll let you know what I find.

newdude Senior Enthusiast

newdude

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Willing to bet that your steering angle position sensor has failed. Somewhat common. Steering column has to come out to change it.

Sam 2012 Tahoe Enthusiast

Sam 2012 Tahoe

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15HDriver - Yes, when I took it in last week, the only code they got on it was the steering angle sensor (because they didn't get it to fail), and the service bulletin said to lubricate it with grease, which they did. didn't make any difference. The sensor may have been failing and is now worse. The confusing part is the engine/trans temp correlation. Very strange. I'm going to drive it enough to get the fail again and then go straight to Chevrolet and have them read the code before shutting it off (the error resets). Thanks for your reply.

  • 1 month later...
Sam 2012 Tahoe Enthusiast

Sam 2012 Tahoe

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2/18 update - on Monday, 2/15, I took my truck to the Chevrolet dealer while the error was showing. Sure enough, the codes showed a bad steering position sensor, and the technician said he was not getting a good signal through the connector either. So, today, they replaced the sensor and connector, and so far it is clean.

 

 

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