2008 GMC Yukon XL Electrical Issues.
For some reason the car sometimes goes dead after you turn it off as if the battery were dead. I can always tell when it is going to happen because the radio will turn off as soon as you turn the engine off, instead of when you open the door. When this happens, I can barely wiggle the negative battery cable and it comes back to life. I have already replaced the battery cable to no avail.
While driving down the road I can roll two windows down at once and the entire electrical system resets. The radio shuts down, the a/c turns off and the dash goes dead. Everything comes right back on but you get the door ding sound like when you first turn the car on and the ac will reset everything to 74°. Sometimes the radio just turns off and back on for no reason at all.
Could this be an issue with the alternator? I'm really at a loss here and don't want to just throw money at the problem without some direction on where to start.
First make sure battery is good,check connection,s at the starter it self,then check the alternator,connection,s,then check the alternator to make sure it is charging right.
Just to add,make sure the ground wire from the battery is grounded to frame good.
I just replaced the ground cable from battery. It is grounded well to the frame. I had the alternator checked at the parts house and they said it was fine, but battery was a little low. The battery is about 1 year old. It was a warranty replacement for another battery that was about 2 years old.
I think you may need a new battery.
Thanks for your replies. I will check it. Let me ask you this. Once the vehicle is running, shouldn't the laternator and voltage regulator supply enough power to operate the electronis without a battery? I know in the old days, you could take the battery out once the vehicle was running. Don't know if that's still the case with all the electronics now days. Reason I ask, there are time when my voltage gauge will drop from about 14 to about 9 while the vehicle is running. Lights will dim, wipers will move slow, etcetera. I have no doubt the battery is a liitle low, but is that the cause of the problem or a result of the problem? Being able to jiggle the negative battery cable when it loses power puzzles me. The battery should either be dead, or not. This is why I thought it might not be a battery problem.
Not with all the power assccoeries you have in the yukon,alternator will not tote them alone,have to have good battery.
All so have the alternator checked again,weak battery may have made it weak all so.
I had the battery checked this morning and it has a bad cell. This does not suprise me as this will be my 3rd battery in 4 years. The alternator checked out fine. I don't think the bad abttery is the cause of the problem, I think it is a result of another problem. I have done a lot of searching and finally found where someone else was having the same problem, but no solution. It can be found here. http://www.tahoeyukonforum.com/forum/showthread.php?t=27420 People have had the BCM reflashed or replaced, replaced the mega fuse, replaced battery cables, alternators. I'm at a loss here. Any advice?
I am having the exact same problem with my '06 Yukon XL Denali. It started last Thursday with the truck having no power at all, not even lights on the dash. Replaced the battery and it started instantly. My wife just called me to tell the truck is completely dead again, nothing will work. I don't know what to do. I've heard of the starter solenoid, fuse, battery, ignition, etc. I'm trying to avoid the $400-$500 service bill but cannot find any fixes that seem worth pursuing. Any help would be very much appreciated.
I am having the same problems with my 2008 Yukon Denali XL. A friend of mine has a 2010 Tahoe and he said he was having the same electrical problems. I came upon this forum because I Googled to find a solution. I been to three different GM dealers and since the problem doesn't happen while I am at their shop they tell me everything is fine. EVERYTHING IS NOT FINE. Sometimes I walk to my car and none of the electronics work. I wait about ten minutes and without me doing anything other than trying to start again everything works normal. I bought a new Optima battery and I still get the electrical problems. In the past few months my Yukon electrical system has shut down on me three times while I was on the highway. The meters will go crazy and the radio and A/C goes out right before all electrical goes out. I had to pull to the side of the road and wait a few minutes. Then all of a sudden everything comes back on. I would like to know what the problem is so I can get it fixed. I don't want to pay for repairs taht do not fix the problem.
My 2008 Yukon XL Denali had the same issue of being completely dead out of no where. I could fix it instantly by wiggling the ground cable (you could here a click) and all would come back to life. I replaced my ground cable w/remote wire (pain to get to the end of that wire where hooks to front of frame). I haven't had the problem since. Since I have done that now the right front turn signal light and left front head light and fog light dim at same time intermittently. I have replaced all on both sides. I'm wondering if the new ground cable is bad or not big enough (cheap part)? If anyone has an idea on that please share, I'm pulling out what little hair I have left with the electrical gremlins.
Forgot since the ground cable repalcement it also says my hood is open sometimes. My wife ran the wiper fluid most of the way out and now they don't completely shut off.
I'm having similar problems with my 2005 Yukon xl denali. I have to jump the truck with a portable battery charger every time I start the truck and, when I turn the truck off, it loses all power. The truck is completely dead until I jump it again to start it.
Oh. I forgot to mention. I have a brand new battery in the car and the car goes dead after I cut it off after having to start it with a portable battery charger. I've put in 6 new batteries in the last 6 months. I've had the alternator checked 3 times and am told that it's fine but the batteries keep being killed.
It was my main ground cable, my nagging issues were cause by a small ground wire that is bolted to the frame with the remote wire from the main ground cable. When I replaced mine the first time, with limited vision to the remote wire buried at the front of the frame I didn't notice that the bolt was holding an additional ground for other items in the car. Once i noticed and re-grounded ALL of my electrical issues stopped. I haven't had any issues since. If you want to save a ton of money and are slightly mechanically inclined, spend the $40 for a new ground cable and replace it yourself. If this is the problem and you take it to the dealer, it won't show up on any test if it's not shorting at that exact time.
@TK76 That is interesting. When I replace my ground cable, I actually grounded it to a new spot on the frame because I couldn't trace where the old one was attached. It looked like I would have to remove the front bumper to get to it. I didn't realize there were other cables that terminated there as well. I will look into this. Did you have to remove the bumper to gain access?
For better visibility it would be nice, but way to much work. The wire runs down the top of the frame rail and goes over the front and bolts to the front of frame. You have to access from underneath, but nothing to remove. You need a small/short 10mm open/box wrench. It's hard to see (will need a light of some sort) and can see the threaded end coming though the frame. If you position yourself right ( I laid parallel with the bumper with my head towards driver side looking towards the passenger side. You should be able to just see the bolt head from there. Jack up the front to give yourself some elbow room. Its a tight fit to get to the bolt so have some patients. Hopefully this helps you out.
I'm definitely going to look at this, thank you for the information. I'll let you know how it goes.
I'll have to take a look at that, thank you for the information. I'll let you know how it goes.
Did everyone trade their Denalis off or did someone find a fix to the issue?
I just bought a 2003 yukon xl and I'm having sporadic electrical issues. It always starts with the ABS light coming on and then it will dead pedal while driving and the Reduced Engine Power light comes up on the dash. I can completely restart and it will run fine for a period of time. It's even caused the locks to act whacky and the guages to shut off. I've messed with the ground cable and this will sometimes solve the issue for a short period of time. Usually when I hit a bump at some point down the road the ABS light will turn on and the process starts again. It sounds like a ground issue to me and I've checked the grounds that I know to, but I was told by a good auto electrician that it is not. Any help would be appreciated.
I'm not sure if yours falls in the right time period for the problem that I was having. I believe it's 2007 and newer. The ground cable looks fine, but it eats itself from the inside. A new cable through Napa or Auto Zone is like $45. You don't want to just throw money at it, but it's a pretty cheap test considering electrical issues can be extremely expensive. If you go that route be careful if it grounds in two spots.The second ground can have multiple things attached to the same spot that are hard to see.
Looking for a Used Yukon XL in your area?
CarGurus has 6,739 nationwide Yukon XL listings starting at $2,495.
Search GMC Yukon XL Questions
GMC Yukon XL Experts