One problem related to wiring has been reported for the 2009 GMC Yukon. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2009 GMC Yukon based on all problems reported for the 2009 Yukon.
My 2009 GMC Yukon xl has had multiple issues with the "reduced power" message. Not only is this affecting the driveability of our vehicle but also the saftey of my fmaily since this is our family car and my wife usually is driving it with out four children in it. It all started in August when the reduced power message came on for my wife with service stabilitrac and traction control, whicle she was driving our kids to school. The dealer said it was "rodent damage" to the throttle body wiring and replaced the connector. About a month later the same exact thing happened when she was going home from the kids school. The code that was scanned was p0335 crankshaft position sensor failure. The crankshaft position sensor was unplugged and reseated and the lights went away. On 10/6 the lights and reduced power message came back on, too the vehicle to the dealership and they could not find any issues "no defect found" tac case # 71-995354643. This has been an ongoing issue and with the chance of my wife and kids being stranded in the middle of no where or broke down on the side of the road is not something that I want from a car that is still under warranty! not only is this car dangerous but also a headache! I called gm customer service and the regional representitive told me that if the car is not doing anything right now then there is nothing they can do for me. I know that other people have this problem as well, I just want everyone to know and hopefully someone can get this fixed!.