2012 GMC Sierra 2500 HD Problems
RepairPal has identified the most common problems with the 2012 GMC Sierra 2500 HD based on complaints from actual vehicle owners. We'll tell you what the problem is and what it'll take to fix it.
The speedometer or other instrument panel gauge may begin to work erratically at times. Our technicians tell us that the instrument cluster must be sent to a repair facility to correct this fault. The warranty has been extended on some of these units to 7 years or 70,000 miles.
The GMC Sierra 2500 HD uses a throttle position sensor (TPS) which commonly fails and causes:
- Check engine light illumination
- Reduced Power message
- OBD trouble code P2135
This issue is related to the throttle position sensor, and can be caused by faulty wiring to the TPS, bad connection at the TPS, or a failed TPS.
To correct this issue, the wiring harness, connector, and throttle position sensor must be inspected, tested, and/or replaced. The most common cause is a faulty TPS.