I am trying to perform a case learn on my swap but I cannot get the scanner to read neutral or park . I have 4 wires from the pcm ..yellow, white,gray, black/w. I tried grounding all the wires, some of the wires . No change. With key on engine off , scanner shows 3rd gear and when I start it it shows quickly 2 then 1 . No combination of grounding the wires changes this. I also show code P0706 trans range sensor circuit. Is there more to it than just grounding wires? I want to do this because I have replaced the engine and I have a few different pcm's I am trying. 2 different pcm's same thing.
thanks wheelie

There could be one of two possibilities you may be encountering here, so please read both below.

ISSUE 1: Your 1997 PCM may not support the CASE Learn function. Some did, some did not. If your PCM is not setting a P1336 code, then you shouldn't need to do a CASE Learn and doing a CASE Learn may not be possible with your PCM.

ISSUE 2: You may not be grounding the correct wires, or the presence of other trouble codes may be preventing the CASE Learn function from being enabled. On the 1997 PCM, you need to ground the blk/wht wire going to C1-69 and the wht wire going to C1-72 to fool the PCM into thinking the transmission is in park. The PCM may also want to see a change of state on the TCC brake switch input terminal, pin C1-67. This signal needs to show 12v + voltage with key on and drop to 0 volts when you press on the brake pedal. But if you are using a manual transmission and the PCM is not custom tuned to work with a manual, codes will set and these may prevent a CASE Learn from being done.

Let me know what you come up with.

-ryan

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