wayneg1035

Just got a 4L80E transmission with a TCI TCU 377500. There is an ouput wire (orange) for speedometer output on the TCU module. I have tried to hook it up to the vss wires from the 4L60E harness. The speedometer doesn't work. My next try is to connect the orange output to the green/white wire from the pcm labelled speedometer/cruise control. Has anyone already done this or know the correct connection to make the speedo work?
Thanks

Injuneer

The PCM requires a signal and a ground from the VSS.

wayneg1035

yeah originally the transmission shop piggybacked both vss out wires on the 4L80E wires to the yellow and purple pcm from the 4L60E, but that didn't work. I did hookup the orange wire from the TCI TCU to the green/white speedo/cruise wire and now the speedo and cruise control work.