2007 Hummer H3 - Whilte driving the dash went crazy. Gas gauge went to empty, temp gauge down to cold. All lights come on dash. Warnings show Gas Empty, Traction control fault all the warnings display one after another. The car still drives normal. Couple minutes later all came back to normal. Next day went to start did the same thing, but would not even crank at all. Turn on and off couple times then starts right up. Drive down the road and it did it again. Dash goes crazy, but car drives normal. Now I never know when it will not start. I replaced both of the crap terminals Hummer puts on with good ones. I replaced the ignition sensor and wil still do it.
I don't think it has to do with the passlock problem everyone else has since it won't even crank when it does it. Then when it does it driving it still drives normal just all lights on. When goes back to normal passlock light is on and battery light. Until you turn off and start again. Then goes away. Next day starts fine then when I go to leave it all faults out like this and can't put it in gear? Then went back to normal and drove it home perfect. WT? I can't find anyone on the net that had this problem. All passlock 10 min problems. Any ideas would be great! I did make a youtube video.
The car does have a full tank. Temp gauge and gas gauge don't move when this happens. NO CRANK at all.

 

How long have you had this truck before it started with the described problem(s)? Any recent work done just before the problems?

Are you still using the crappy OEM Battery Terminal Connectors. If so, hack them off ASAP and replace with a quality aftermarket set like Stingers or your favorite brand. #1 mod to do to every H3/H3T, know cause for electrical issues, cheap and easy to rule out. permanently.

 

Do you have a sunroof?

 

Thanks for reply. I have had it little over a year now. No problems. Just happened first time on a cold morning after driving about 15 miles. When dash went crazy. My son said your out of gas. I said NO. Something wrong. Then it went back to normal. It will drive perfect for couple days. Then do it again. I did change both terminals. Tested battery and altenator. I know it's not the starter or alt because it will run perfect when it works.

 

yes. I haven't used it in a couple of months. I live in Michigan;}

 

Replace the battery.

 

To same me $160 I just got home with my 2014 expedition and took the battery out. Put it in hummer and it hasn't changed anything. Same problem. No power to gauges and won't even try to start. I think it has to be something in ignition or relays. Replacing ignition sensor did not change anything. I don't think it is the full ignition chamber. Maybe that magnetic sensor to the right of the igniton. Has the magnetic rod that moves when you turn on key.

 

Take a look at your UFB. Make sure to be prepared:

 

Just tried again. Now I can't get it to start at all.

 

Clean connector/ignition switch.