Possible bad PCM

I need help diagnosing a bad PCM. This summer my tack gauge stopped working and the truck stopped charging. So I changed the cps and that fixed it. Well about a month ago the same thing happen for one day then went away. Now it's been shifting weird. The truck doesn't start to move till I hit 2000 rpms. It also doesn't shift right and will lurch when it should be shifting sometimes. Once it does finally shift I don't have overdrive. And now the no tack and no charging issue is back also. Do these sound like PCM issues or something else?

i am fighting a very similar issue right now and it has been very frustrating. i have been messing with it since june. clean grounds, voltage at cps, check fuses. i have no guages at all, no charging, no OD and no lockup. i have cleaned all my grounds, traced wires, voltage at all 5 volt sensors, new pcm, guage cluster self check was fine. good luck, if you find anything let me know and i will do the same.

Well at least someone else is having the same problem. I think I'm going to change the PCM and check all the grounds. Hopefully that helps.

jkretzer said:

i am fighting a very similar issue right now and it has been very frustrating. i have been messing with it since june. clean grounds, voltage at cps, check fuses. i have no guages at all, no charging, no OD and no lockup. i have cleaned all my grounds, traced wires, voltage at all 5 volt sensors, new pcm, guage cluster self check was fine. good luck, if you find anything let me know and i will do the same.

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I had the exact same problem after fitting a 2low kit checked everything all the usual suspects and nothing! Turned out to be a bad connection to the rear/below of the gauge cluster.