my buddy has and 05' he tried to put a head unit in it and now the tcm is messed up. it keeps giving me codes about no communication with the tcm or something about the main circuit connection mismatched. he for got to dis connect the battery when he did the swap and he pulled 2 ignition fuses out of the fuse block in the side of the dash. Truck still will not start even with the original stereo re-installed.

Could this have tried the tcm or does it just need to be reflashed? any ideas thanks