2003 GMC Yukon Denali: headlights failing or too dim

Filed Jun 8, 2015 · Driver assistance, Electrical · 82,000 miles · MO

Truck started to have major eletrical issues. Blubs burning out often sockets burning out had to replace too often. Light covers melting. Headlights out and will not come back on for days, have to tap them to get them to come back on. Horn blows from alarm all times of the day and night. Inside lights on dash, steering wheel and doors will not work at times all lights are not functioning correctly. Lights at times too often will not work at all. Stability warning light comes often. Afraid truck will catch fire from the electrical issues.. Please help!!!!

Filed Dec 16, 2011 · Driver assistance, Electrical · 97,000 miles · GA

I have had multiple ongoing electrical issues with this vehicle. Starting in 2005, the exterior electronics (I.e. Signal lights, stop lights, head lights, etc) began to malfunction. For example, I would trigger the signal for one direction and all of the signals for all directions would trigger... Even pressing the brakes triggered all of the exterior signals. The dealer had a hard time isolating my problem, but after several visits, the dealer was finally able to diagnose and rectify it... They isolated it to a junction box where all of the electronics terminate. However, by this time, my vehicle was out of warranty, so I had to cover the costs for repairing the problem myself. My most recent issues, which, by the way, seem to be common issues, are triggered by a message stating, "reduced engine power". This particular issue does not always render the same results... Sometimes the vehicle's speed will significantly decrease to nearly a halt, but other times I may just experience increased idling of the engine, even if I am at a complete stop. My understanding, according to hundreds of reports that I have read on the message boards, is that this issue is caused by either a wiring harness that leads from the accelerator to the throttle body or it's a defective throttle body altogether. I have experienced intermittent electrical problems with my windows as well, but this appears to be a minor issue when compared to the other two that I addressed above. I will file a formal complaint with gmc corporate office today and see where that goes.

Filed Feb 20, 2007 · Electrical · WI

Headlight flicker had dealer work on it and replace one headlight but this did not correct the problem. Dealer said this was normal. Notice the flicker when I go over bumps or when cornering to the left.

Filed Feb 15, 2006 · Electrical · 18,000 miles · KY

After noticing that my 2003 yukon denali had intermittent headlights/dash lights dimming, I took the vehicle to my local dealer to have it checked out. They presented me with a document that stated the gm stated this was not a malfunction and was a normal condition. There is nothing about this that is "normal". Any time, at night, a curve is taken at above 35 MPH the lights flicker. I had already pinpointed that it had to do with the vses system because when the vses is turned off, this does not happen. When a curve is taken and the flickering occurs, the voltage meter for the battery drops substantially and then goes right back to normal. This is a distraction for the driver (myself), any oncoming traffic, and anyone that I am behind. This absolutely needs to be looked into before it causes injury.

Filed Sep 23, 2004 · Lights · 10 miles · CA

Head light flicker while driving and turning or going over bumps. Appears to make drivers think I am flashing my high beams. Dealer could not duplicate problem. Very distracting while driving, not only to me but people who are ahead of me. Dealer was not very concerned about problem and sent me on my way. I feel like this is a safety issue and should be taken care of. This is not an intermittent problem, it happens every time I drive at night.

Filed Apr 19, 2004 · Electrical, Lights · 3,000 miles · MO

While driving at night the headlights and dash lights flicker off and on. This condition only occurs while traveling at speeds above 35 MPH and when hitting a bump or making a curve. This condition is not only distracting, but when driving at night with no other ambient light I am unable to see adequately ahead of my vehicle. I have had drivers ahead of me pull over thinking that I was flashing my lights at them and other drivers get irate believing that I am "bright lighting them". This is a safety issue that appears to be widespread on the denali's with stabilitrak. Gm states that this condition is "normal". I believe that headlights are meant to burn steady and not flicker off and on. I am requesting that the federal safety agency investigate this with the auto manufacturer to mandate a fix before there are injuries attributed to this condition.

Filed Apr 11, 2004 · Electrical · 256 miles · OR

Headlights flash when turning at speeds over approximately 35 MPH. These incidents have caused road rage with other drivers. Apparently, other drivers feel I'm flashing my bright lights at them.

Filed Jan 29, 2004 · Lights · 7,000 miles · NV

'03 yukon denali - while driving in complete darkness while making a left sweeping turn every visible interior light turns of and on for 1-2 sec. This includes headlights. This is becoming very dangerous and distracting to other drivers. The dealer blames it on a loose headlight switch. They replaced it. That did not solve the problem. On another night trip, the same event occured again. The dealer replaced the altenator. It still does it. The dealer says they noe have no idea. I really need help. I'm concerned about complete loss while in darkness and subsequently hitting a divider.