Have changed Computer, switch and Transfer motor...error leaves and then comes back when I hit a bump ...any thoughts?

 

get it scanned.

 

Thnx for the reply...I have already had it scanned on 2 different machines.......Even though the Service 4WD error is displayed , it shows no codes.

 

Was it scanned with a GM Tech2 or MDI scanner? Only a dealer or mechanic with access to GM tools can read drivetrain codes.

 

Actually, I am unsure. All I know is the guy told me it was pretty expensive......lol
He runs a pretty good sized independent shop, so I am not sure...

 

It's also possible that driving over bumps is jostling a loose connection somewhere, and it's triggering a loss of communication. I would re-seat the connector on the transfer case control unit, and inspect the related wires for damage or loose grounding connections.

 

Awesome................I was thinking a loose connection, Because when the light is NOT on, everything shifts smooth as silk....
Will check the wiring.....Thnx for the help...Chris Taylor