Been having a persistent problem with dtc p0650. Can anyone give any info on what to check for to help get rid of this code. I have tried everything I can possibly think of so far and nothing I did worked.
-had cluster bench tested it's good
-replaced pin for mil wire in cluster connector
-replaced cluster connector
-got 2 new batteries
-followed mil wire for its full length couldn't see any abrasions or cuts
-checked all grounds on truck couldn't find any loose
-added additional grounding straps
-sent pcm in to g7 computers they said
They replaced broken resistors and transistors
-checked every fuse in the truck
-checked under fuse block thoroughly
-checked pcm connection

Is there anything else I might be missing here, this is driving me nuts and I can't smog the truck which I need to do by April to register it in my name. PLEASE HELP!!
Thanks and God bless.