Engine swap now u0101

[Dante2795]

Just finished dropping engine back in the truck. Got it running and everything is good besides code u0101. Loss comm with Tcm. Plus no light under gear and brake and abs light are on. I’m thinking ground somewhere but not sure. Tcm was fine before so I don’t see how it would mess up from sitting a month. Any ideas?

 

[jwrkansas]

Try running a ground from a good known source to the heatsink on the backside of the tcm and see what it does.

 

[duramaxnate]

What are the details of the swap?
What year is the truck your working with?
What year/engine of power/drive train are you working with?

 

[Madspeed]

Try running a ground from a good known source to the heatsink on the backside of the tcm and see what it does.

Btw this test tells u no gnd or the gnd inside the tcm is shit

 

[Dante2795]

What are the details of the swap?
What year is the truck your working with?
What year/engine of power/drive train are you working with?

07 lmm. Cracked piston so did lb7 pistons/lbz rods. Not necessarily a swap. Just pulled engine and put back in. Everything is perfectly fine just this Tcm problem. Was fine when I pulled into garage

 

[duramaxnate]

07 lmm. Cracked piston so did lb7 pistons/lbz rods. Everything is perfectly fine just this Tcm problem. Was fine when I pulled into garage

You check your tcm fuse in the fuse box under the hood? The grounds for the modules are on the drivers side of the block.

Sent from my Note 9

 

[zakkb787]

To the OP of he ever comes back, had the a similar issue with my truck with the same code. Losing communication. Do the alligator clip suggestion. This has fixed mine temporarily. I pulled it when replacing my water pump and I guess maybe jarring the connector lose or moving the TCM has broken a connection somewhere.