[RipNTear]

Hello all! I’m new to diesels and this forum. I have a 2011 GMC Sierra 2500 HD.

I’ve been looking for a few pointers on trouble shooting.
The problem: head gasket failure led to a top end rebuild. Was a running truck before now it is not. After getting everything back together, I installed the motor ops switch and then was able to flash the ecu. When I attempted to turn the truck over the gauge cluster went blank with the back lights still illuminated. When the key is returned to the ACC position everything comes back. I have service stabilitrak, service traction control, service 4 wheel drive. No other lights or messages on the dash. Now when I try to re-flash or read the autocal says $0208.

what I’ve done: I rechecked all my connections, and fuses. I unplugged the batteries and replaced them just to make sure it wasn’t the batteries,

mods:
Headgaskts
Studs
Cp3 conversion
Wcfab high flow y bridge
Motor ops switch
Lots of parts replaced but went back with stock(turbo, injectors, hoses, etc)

It seems some have had similar issues, but I haven’t found any exact resolutions to this. I’m guessing that I have something not connected, pinned correctly, or damaged wire somewhere. I will be removing the switch pins and putting the factory ones back in.
Could anyone offer some help?
Thanks!

 

[OkDually]

Welcome to DieselPlace

Have you gone back through all grounds?

 

[RipNTear]

Welcome to DieselPlace

Have you gone back through all grounds?

I have not! That is something I had planned to do! Thank you for reminding me! I did see an eyelet style wire beside the fuse box just hanging out and couldn’t remember if I had done that or not now that I’m thinking about it. If you are looking just to the right of the fuse box facing the fire wall it’s a smaller loom that comes from under the fuse panel. Any idea what this could be? I’ll snap a pic in a few.

 

[OkDually]

I have not! That is something I had planned to do! Thank you for reminding me! I did see an eyelet style wire beside the fuse box just hanging out and couldn’t remember if I had done that or not now that I’m thinking about it. If you are looking just to the right of the fuse box facing the fire wall it’s a smaller loom that comes from under the fuse panel. Any idea what this could be? I’ll snap a pic in a few.

Not exactly sure what it could be.
Take your time and go through all grounds, cleaning the contact areas. If you find any grounds that are in questionable shape, replace them

 

[RipNTear]

Not exactly sure what it could be.
Take your time and go through all grounds, cleaning the contact areas. If you find any grounds that are in questionable shape, replace them

Copy that! I handle that tomorrow for sure and report back.

 

[RipNTear]

@OkDually just wanted to report I found the bad ground and have fixed it! Thanks for the input. These trucks are hella complicated! Now to just get it started!

 

[OkDually]

@OkDually just wanted to report I found the bad ground and have fixed it! Thanks for the input. These trucks are hella complicated! Now to just get it started!

Go through all fuses and make sure things are good on that end

 

[RipNTear]

Ok… I meant to update you guys! Got it started up. Runs great. Thank you all for the help. If anyone else reads this it ended up being a bad ground. Once that was fixed it started right up.

 

[OkDually]

Ok… I meant to update you guys! Got it started up. Runs great. Thank you all for the help. If anyone else reads this it ended up being a bad ground. Once that was fixed it started right up.

Glad you got it resolved.
Thanks for the update!

 

[RipNTear]

Glad you got it resolved.
Thanks for the update!

Thank you for the help!!