Magnum and Wiring Swap

I ran across a tip years ago and saved it. The gist of the tip is that if you turn on the vehicle and then short the CCD or PCI bus wires and then turn it off while it is still shorted, the PCM will stop looking for the VTSS message and start. Assuming the vehicle doesn't have VTSS which would turn it right back on the next time you turn the power on.

If the PCM has never been in a vehicle with VTSS, it doesn't care if the signal is ever sent. Once the PCM is plugged into a vehicle with VTSS and the PCM sees the signal, it will always look for it even if it is then moved to a vehicle that doesn't have it. This is the source of the problem when someone plugs a borrowed known working PCM from a vehicle that didn't have VTSS into a vehicle that does have it, and then tried to put the PCM back into the original vehicle and it no longer starts.

I suspect this is a fail safe mode for the PCM. If the network is shorted before the PCM sees power, it waits for a good signal to do anything? But if the network is shorted while the PCM is powered, if figures something broke and goes into a fail safe mode and stays that way until it sees a good signal on the network?

The only real trick then is wiring in the PCI or CCD buss so you can short it. Even if just temporarily.

Note that I never tried it, so your mileage may vary. It was posted by an automotive technicians forum, so maybe it is legit?

Something else to note, I thought it was an issue with VTSS, not SKIM/SKREEM. Not really sure how they interact. If the SKIM/SKREEM module sends it's own code to the PCM, then it is an issue with those. But if it is an issue with the VTSS system and the PCM looking for a message from the CTM or some other module later on, then it is VTSS.

Either way, it is worth a try.