Has anyone ever had a problem with losing commo with the ficm? I am getting this code since I sent the ficm off to have it redone. now it won't start, and getting the code u0105 which is lost commo with ficm. I took the wiring harness off to check all the ends and wires. Repaced the ficm ends with new onew. When I put it back on the engine hit a couple times and now I have the lost commo code.

 

Are you sure those big plugs are clicking into the FICM? If they are I'd send it back...

I know when you put a FICM on a truck that didn't come from it, you'll get a code like vin mis-match with FICM, but it's a soft code, doesn't throw a light, and doesn't effect the way it starts or runs. Just make sure that thing is plugged in tight and you hear the snaps click on.