Yeah, the new transmissions inserted the switch INSIDE the tranny....had to replace one...PIA!!!!!

You can check the switch:

The circuit coming out of the top of the TCM is the Class II data line to the IPC...this is the data line that tells the PRNDL, which gear it is in....

If you disconnect the harness from the transmission, turn key to on, you should get 12v at F, G, H, J, and W terminals, in the harness.....if no, then you have to check for power and ground to the TCM(if no power at the W terminal, in addition to the others, I would be checking the output from the BCM)....also check that you have a good ground at terminal K in harness....

You can check the IMS(forgot they called it that), by probing the transmission connector(not the harness)....just get ohm readings....attach one lead to terminal K in transmission, and the other lead to terminals(one at a time) F, G, H, J, AND W, and look for the corresponding response as you shift from P to D.....for example, attaching the other lead to W, you should only have zero ohms, when the shifter is in P or N....any other position it should be OL......

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