LBZ: Will Not Turn OFF

[bmc1025]

I have an 06 GMC 3500 SLT CC Dually, It randomly will not turn off and sometimes when it does, the glow plug light and check engine light illuminates. The gauges turn off and then on again, and the turn signals will work with the key out. Engine shuts off when I pull the IGN E fuse, the fuse to the left of it seems to affect it also.

So Far I have tried unplugging while the above lights are on, IGN and engine off:

IGN Switch
Tail light board connectors
Trailer wiring harness at rear of truck
TCM
BCM
Both GP controller plugs

The CHK ENG and GP lights will come on randomly while the truck is sitting undisturbed and run the battery down.

I have checked the trans wiring harness from the fender well to the transmission.

My next step will be pulling apart the under hood fuse box and all wiring next to it.

 

[jlawles2]

Does the truck have an aftermarket alarm?

 

[NC-smokinlmm]

Have you replaced the ignition switch yet?

 

[kivetts04dmax]

I've seen this on a truck that the ground wire going from the back of the head to the firewall wasn't hooked up and sometimes it took forever to shut off

 

[Frankin_truck]

Have you replaced the ignition switch yet?

this worked for me when i has ingnition problems

 

[bmc1025]

No alarm or remote start installed. I will go through and clean all the grounds I can find today.