The other day i was driving to work 55mph straight down the road when all of a suddenly i lost all electric including gauges dirrectionals windows locks radio nav how ever still had climate control lights and gauge lights but all gauges were gone the truck continued to run fine about ten miles later everything came back as soon as it left i couldnt even call the onstar people because the power was gone anybody have any ideas?When i finally was able to contact the onstar people the truck threw no codes but while the power droped out i kept getting service abs,service 4 wheel drive ,emision trouble kept flashing and repeateing

I assume it is on the 2008. Any mods you do it?
I would say a loose wire somewhere to the driver side fuse block. Seems most of those items tie into that location. But some don't but if some modules got un powered it can possible send garbage data around. Either a loose positive or ground. I would not think it to be batteries being 2008 but no idea the mileage on it and how driven. A dead cell can really mess with the modules through out the truck.

Brian

Mounted on the pass firewall is a large fuse bank. One of the nuts holding one of the power wire connections under that cover is loose or one the connections is corroded.

Remove the cover where all the red wires disappear and inspect/ tighten in there. Rememeber to use care not to ground your tool, as there is 1500+ amps of current waiting to make a really crappy light show of sparks.

http://www.dieselplace.com/forum/garageimage.php?do=full&p=100626&d=1256933471

There was an article in one of the GM newsletters a while back, but I can't seem to find it.

That was the item in my mind I say that be the place to check as well.

Brian

That was the item in my mind I say that be the place to check as well.

Brian
I would have had the post first;), but I got called away mid sentence:mad:, and I had a '07.5 in the driveway at the time:D.

Ok :) But what if that is not the issue. :rolleyes: But lets hope and easy fix no matter what. Good info helmccall. Let us know what you find out. But I go with helmccall first. Easier to check than looking through out the truck.

Brian

I am having the same exact issue with my truck. I am going to try this route tomorrow. I'll be sure to post my results. Just a thought, couldn't I disconnect the batteries before the work to avoid the light show of sparks??

That would work.

Mark

Yep, you should be able to just disconnect the grounds and be fine.