2004 GMC Yukon – No Heat

DDaley: I have a 2004 GMC Yukon SLT with 5.3L V8. I’m having an HVAC problem. The vehicle has dual climate controls. When in AC mode occasionally it will start blasting out hot air and the only way to fix is to shut off engine for a little while and it resolves. Ok, so now that … Continue reading “2004 GMC Yukon – No Heat”

2007 GMC Yukon Multiple Misfires-Codes-P0300-P0352-P0354-P0356-P0358

This 2007 GMC Yukon came in with multiple complaints among which were the engine seemed to have no power, the Service Engine Soon, ABS and Traction lights were on and there was a stability message displayed in the Driver’s Information Center (DIC). The customer also stated that the vehicle ran fine sometimes but as soon as the … Continue reading “2007 GMC Yukon Multiple Misfires-Codes-P0300-P0352-P0354-P0356-P0358”

2008 GMC Sierra Denali, Multiple Electrical Problems

This 2008 GMC Sierra Denali came in with multiple electrical complaints. The blower did not work. The left side stoplight, all left side turn signals, the right side mirror turn indicator. All of the power windows except for the right rear window did not work. There were a multitude of codes scattered through various modules. … Continue reading “2008 GMC Sierra Denali, Multiple Electrical Problems”

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”

2004 GMC Yukon, Power Windows & Seats Inop, Airbag Light Is On

This GMC Yukon came in with the complaint that the power windows and power seats did not work and the Airbag light was on. Checking the fuses found that the SIR or airbag light 15 amp fuse was blown. I also found that the 50 amp MBEC fuse was blown. I replaced both fuses and … Continue reading “2004 GMC Yukon, Power Windows & Seats Inop, Airbag Light Is On”

2007 GMC Envoy Denali, Blower Does Not Work On Any Speed

This 2007 GMC Envoy Denali came in with the complaint that the blower motor would not work. The customer stated that they had removed the blower motor and connected it to battery voltage and ground. The blower motor worked under this condition. This vehicle also has auto temperature controls as indicated by a digital display. … Continue reading “2007 GMC Envoy Denali, Blower Does Not Work On Any Speed”

1994 Chevrolet C1500 Blower Inop/Erratic

This 1994 Chevrolet C1500 came in with the complaint that the blower motor either would not work or work sometimes. A quick check of power and ground at the blower motor itself revealed a lack of ground while the problem was present. With the system on high and the blower motor not working I touched … Continue reading “1994 Chevrolet C1500 Blower Inop/Erratic”

1992 GMC Pickup, Changing The Blower Motor

This 1992 GMC C1500 pickup came in with the complaint that the blower motor was squeaking and the noise was getting worse. The blower motor is located under the passenger side of the dash and has this rubber and foam sound deadening cover over it. I know it seems strange but the first step in … Continue reading “1992 GMC Pickup, Changing The Blower Motor”

2005 GMC Sierra, Lights Flicker or Pulsate

This 2005 GMC Sierra came in with the complaint that when the vehicle is started cold, the headlights, dash lights and dome light will flicker or pulsate. As the system runs the problem diminishes but never goes fully away. This is a common complaint on many Cadillac, Chevrolet and GMC full sized trucks and suv’s. … Continue reading “2005 GMC Sierra, Lights Flicker or Pulsate”

2006 GMC Yukon, P0449

This 2006 GMC Yukon came in with the Service Engine Soon (SES) light on and a code P0449 stored in the PCM memory. This test should be done on the vehicle but I could not figure a way to o the test and position everything for a good picture. So you will just have to … Continue reading “2006 GMC Yukon, P0449”