PLEASE HELP!!!!

[thethorninmyside]

Hopefully not major but issues none the less. In desperate need of help.....I own a 2017 GMC SIERRA

install a sub and amp duo package with lp7 converter. Once 99% complete started truck everything worked. Turned truck off and connected power cable to battery. Truck now won't start all aftermarket lighting still works, key fob and alarm still work and one headlight strangely enough still works. truck is 100% unresponsive as far as rolling over or signs of life at all besides previously stated........ anything is a help at this point?????????  

[Black02Silverado]

I take it you checked every fuse ?

[thethorninmyside]

no heading to that now just wondering if anyone could shoot me in the correct area of the truck id be looking for the issue. Could a fuse make everything unresponsive except aftermarket lights, one head light and the alarm?

[Black02Silverado]

Electrical issues are a pain to trouble shoot.  So many things can make weird things happen.  I hate spark chasing.   You disconnected the battery before you installed it correct?  If so maybe something grounded.