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Lb7 electrical problems

aadd1998

By aadd1998
in Duramax Diesel & 8.1L Big Block

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aadd1998 Enthusiast

aadd1998

Posted
Posted

I just did a complete frame off on my 02, including having the cab stripped bare, dash and everything out. It was back together and everything working fine. Out of the blue I got tons of issues like windows, radio, hvac, horn and pretty much everything else just not working. The gauge cluster has both turn signal indicators lit up, and a couple other random lights all the time key on or off. The truck will start with the key but will not turn off. Have to pull igniton relay to kill it. I have communication with the ecm but nothing with any other module on the truck. I tore the truck apart unplugging things 1 at a time with no results. The only thing I've found so far is when you mess with the headlight switch some stuff will start to work like the horn and the key will kill the truck. But when you do that there is a relay under the dash labeled inadv pwr that buzzes constantly. I dont know what to do at this point

 

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  • 1 month later...
fdgefrts New Member

fdgefrts

Posted
Posted

Try tapping a jumper from the battery ground to every known good ground on the cab and see if any of these repair the issue. Everything being on like that sounds like a weak ground causing power to leak all over the place. We see this frequently on the trucks I help troubleshoot. 

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