2008 GMC Yukon, Reduced Power Mode, Code P0641 00 Stored

This 2008 GMC Yukon came in with the complaint of reduced power and the vehicle could not be driven over about 35 mph. There were a lot of codes stored but the only one of real relevance was Code P0641 Symptom 00, 5 volt reference circuit 1.  I looked at data under the TAC section … Continue reading “2008 GMC Yukon, Reduced Power Mode, Code P0641 00 Stored”