Dead Battery Issue

[joetama]

Well it's been a while since I've been back here.

I have been dealing with this dead battery issue for the last few years now and I'm finally sick of it. Today I got the Fluke meter out and put it in Amp mode and hooked it up in series with the battery.

Begin the elemeination process. Have everything down to about 500 mA and start pulling fuses. Get to M28 and bam almost 0 mA. Pull the cover look and find M28 PCM/TRANS FEED.

Any ideas on this one? I'm not sure where to proceed.

 

[Hootbro]

I do not know which transmission you got but I would look up the schematic here at https://techauthorityonlinedemo.extra.chrysler.com/service/repair/wiring/view/classic.htm.

Leaving the C1 connector on the PCM, I would start disconnecting the other connectors to see if the draw goes away to narrow down some more. If it does not go away, remove the C1 connector and if it goes away, probably got a PCM issue, if it stays, you got a wiring issue between the C1 connector on the PCM and the C1 connector on the TIPM.

I really do not know the logic of the PCM so I cannot rule out a slight parasitic draw as being normal or not normal. 500 mA does seem a little high regardless though.

 

[Tach_tech]

500miliamp is quite excessive, usually it should be around 50 or lower. How long did you leave the fluke hooked up before you started pulling fuses? Some modules may take up to a few minutes before they go into sleep mode.

 

[joetama]

It goes down to 500 mA after about maybe 5-10 minutes. I left the meter hooked up and kept refreshing it (sleep timer) for about 2 hours till I started yanking fuses.

When I say about 0 it's really 50 mA which from what I read is pretty standard for background operation.

I pulled the fuse last night when I parked the truck. This morning she fired right up!