What's Going On?

[nick-o]

Long story short, my dad has got the 2007 Youkon XL, and a couple of mornings ago he went to start it and the battery was completely dead. He said the interior lights didn't even work.

 

Now, I would've thought nothing of it, but the same time last year this same thing happened. Just one morning the battery was dead and then it was fine after it was jumped.

 

He swaers that the doors were closed and all lights were off, so I don't know whats going on.

 

Just wanted to see what people thought. Has it happened to you?

[jrrod2004]

Long story short, my dad has got the 2007 Youkon XL, and a couple of mornings ago he went to start it and the battery was completely dead. He said the interior lights didn't even work.

 

Now, I would've thought nothing of it, but the same time last year this same thing happened. Just one morning the battery was dead and then it was fine after it was jumped.

 

He swaers that the doors were closed and all lights were off, so I don't know whats going on.

 

Just wanted to see what people thought. Has it happened to you?

 

 

the GMT900 trucks utilize the GMLAN system which allows them to talk to each other even when the vehicle is off and the key is out of the ignition. A known issue is the HVAC control module staying on for an extended period of time as well as some other components. I would have him take that vehicle into the dealership to do an overnight evaluation. When the truck is off for more than 4 hours, it should pull anyway from 50 milliamps to 100 milliamps (depending on the level of equipment installed from the factory). This should be the consistent draw on the battery for the entire night but if it is higher, then one of the components is defective and needs reprogramming or replacement.

 

If it is a GMT 800 series truck, then this is unusual as these trucks do not have the GM LAN so the components really dont communicate with each other

[nick-o]

Should it be easy for the dealership to find the problem. Also, is it a widley known problem, because when it happened last year, he took it in, and the mechanics only checked the battery and said it looked fine. Last, do you think there is a reason for it happening only once a year roughly at the same time.

 

Thanks for all of the info.