I have a 01 Durango SLT 4WD that is draining the battery. I have replaced both the battery (standard life expectancy) and the alternator (bad diode string) and now have determined that when I leave fuse A (labeled 4x4) in the PDC installed & the 2/4/hi-lo switch (dash-mounted) in 2WD - there is a parasitic current draw of 95 - 110 ma.

When I pull fuse A, the current drops to around 18 - 20 ma.

When I switch the 2/4/hi-lo selector to 4-hi and reinstall fuse A - the current stays around 26 - 30 ma.

The basic Chilton schematics for Fuse A shows that it is strictly for the TCCM, but I am not 100% sure.

Has anyone seen this problem before, and does anyone think I also need to investigate the PCM..... or should I just go burn $50 and get a junk yard TCCM replacement?

 

It's not the PCM most likely. That is usually the last thing to look at. It sounds like you have some knowledge in electrical testing so use it and follow your circuit it could be as simple as a short or a bad switch. Most everything running through the PCM is ground controlled. I would woould start at the ground side of the circuit if that is the case to check for a short on the ground side or a bad switch/relay.

 

Electric 4X4 actuator switch on the transfer case contacts are grounding. I would replace the actuator. There should not be anything else on there.