One problem related to dash wiring has been reported for the 2005 GMC Sierra 1500. The most recently reported issues are listed below. Please also check out the statistics and reliability analysis of the 2005 GMC Sierra 1500 based on all problems reported for the 2005 Sierra 1500.
Fan speed 5 will not work and speed 4 smell like burning wires, drivers temp control will not work only cold air. Connector under passenger side fan black wire burned into and melted connector. GMC parts man said there was a national backorder on parts because so many wes go bad.