Engine/Transmission (1998.5 - 2002) Ecm or Pcm powering gauges

[MKopf]

Both my oil pressure and temp gauges went out on my truck so I took it to the dealer and they said my Pcm was bad. Problem is manual says the power for those 2 gauges comes from Ecm. can it be the Pcm? Thanks for the help Mark.

 

[JLandry]

Mark,



It could indeed be the PCM...



The gauges themselves are controlled by a computer on the back of the instrument cluster. The instrument cluster gets told what to put on the gauges by messages it receives from the PCM over a communications network (the Chrysler CCD bus). The PCM in turn gets oil pressure and temperature information from the ECM over the same network.



So assuming the dealer has determined nothing is wrong with the oil pressure or coolant temp sensors, the communications network or the instrument cluster, it's not unreasonable to conclude something must be wrong with the PCM.



Good luck!



John L.

 

[MKopf]

Ok sounds good now I just need to get a PCM. Anyone know where to get one or just bring it to dealer they want $650 for the PCM and install

 

[JLandry]

Mark,

That sounds like a reasonable price *if* the dealer will guarantee it'll fix the problem. You can buy a used replacement PCM from Auto Computer Exchange for $495, but that's a gamble with no assurance it'll fix the problem. Also, sometimes Auto Computer Exchange can be problematic to deal with... Do a search here on the forum and you'll find both praises and horror stories for them.

Best regards,

John L.