[overthinker_tinkerer]

Hey there,

I have a parasitic draw on my battery and I narrowed down what circuits are drawing the current. I discovered the draw because my Walmart brand car battery would discharge to 10 Volts in two days. I know Walmart batteries are garbage but I just picked this one up a year and a half ago so I doubt it was failing. I charged it up 100% and then drove to an Autozone where I had it tested. Battery checked up to be good with 75% of its life left. This hard truth reassured my suspicions so I hooked up my DMM and started measuring. Once all of the systems go to sleep the overall draw was 91mA. This is 41mA over the well known threshold of 50mA. I've even seen from posts in other places that I should be down near 35mA, for Commanders at least...

I started pulling fuses and here is what I found: When I pull the IOD fuses out of circuit, the draw drops down to 74mA. KEEPING THE IOD FUSES OUT, when I pull either the JB fuse or the REAR WIPER/IGN R.O. fuse, the draw drops to 0 or ~1mA. This is in the fuse box under the hood.

So now I'm in the interior fuse box or JB: WITH THE IOD FUSES STILL OUT, I'm getting a response similar to the one I get when pulling the fuses from the box underneath the hood. When either fuse #12 (Mem.Sw, Courtesy Lamp (B+)) or fuse #16 (SCM, Cluster OBD (B+)) is removed, the draw again drops to 0 or ~1mA

I have no literature or manuals that can provide the circuit diagrams I need to find out what's part of these circuits so I'm pretty lost. Hopefully someone on here has the knowledge of these circuits that I don't to piece together and suggest a troubleshooting idea... I'd really appreciate that.

Notes: I have not replaced the faulty ignition switch from the factory and it has caused my dash to light up like a Christmas Tree multiple times before. The module in the passenger door is also unresponsive and has been ever since I've owned the car (owned Commander for 4 years so far and haven't had this issue before). Courtesy lights are not triggered when the door is open. There is also no "PASSENGER DOOR OPEN" message on the EVIC, so it is definitely not communicating. There is also a short in the multi-function switch that controls the blinkers, high-low beams, etc. Sometimes the courtesy lights turn on randomly and start to flicker from the intermittent short in the switch. I give the switch a good jiggle and the lights go back to their normal operation. My sunroof drain also clogged up before and started causing my driver side carpet to start soaking up with water. Keep in mind all of these issues existed up to years before I started having this issue, so I have my doubts if these malfunctions could be the cause.

 

[Up4XK]

I think that the drain clog could be part of the reason. Likely not the first time water has run down the pillars, and sometimes it's a build up of corrosion. doesn't take much to disrupt the CAN. You said you have had it for 4 years? Do you know the Jeep's history? May have been one of those Hurricane Sandy flooded cars. Again corrosion build up.

 

[Wombler]

I think that the drain clog could be part of the reason. Likely not the first time water has run down the pillars, and sometimes it's a build up of corrosion. doesn't take much to disrupt the CAN. You said you have had it for 4 years? Do you know the Jeep's history? May have been one of those Hurricane Sandy flooded cars. Again corrosion build up.

My understanding, and personal experience, with the drain clog is that it happens at the bottom, not the top. The nipple at the bottom clogs, so the water comes out at the bottom where the hose goes into the nipple. Not out the top to run down the pillars. But, I could be wrong. Either way, there shouldn't be any connectors in the pillars....you'd never be able to get to them, they'll be at the top or bottom.
Regardless, I agree with the possibility of corrosion that has gotten worse over time....

On top of that, everything in the "Notes" at the end of OP's post makes me cringe a little....that is a LOT of electrical problems from areas that are all looped in to the CAN bus. Yes, these issues have been there for years without causing a parasitic draw, but the inherent "issue" with complicated multiplex circuits like the CAN bus is that it requires specific voltages and resistances all over the place. One issue of the right size can cause a cascade effect of other issues down the line. Sometimes this takes time as things stack up.....and this could be because of corrosion.
I'd already rule the ignition switch out, this draw is happening with the key off...and that's already what the switch would do on its own :lol: I'd bet this is all something in your door switches, their circuits or the multi-function switch. Both are active all the time even key out. The multi-function switch plugs directly into the clock-spring & steering angle sensor housing which is all one big integrated unit (the SCM) that is fed by the CAN bus. Fortunately, that switch is fairly easy to replace and shouldn't be too expensive. The clock-spring unit is around $600+, however....but I really doubt there's anything wrong with that.

Since you don't have any reference material, maybe this will help a little with sorting out fuses:
IOD fuses are "Ignition Off Draw" these should make up your ideal ~30mA, things like radio memory, dome light triggers, etc.
R.O. fuses are "Run Only"....meaning, only when the Key is in the Run position.

Your Rear Wiper and Ignition holding 70mA is interesting, but the big ones are your interior fuses....#12 pointing right to Door Light triggers (Courtesy Lamp), and #16 is your OBD (on board diagnostics) gauge cluster (should be all the stuff that shows up on the gauges when you open doors with the key off), and Steering Control Module (SCM)....this could ALL be just because of that multi-function switch....but it could still be a lot of things....

 

[Up4XK]

Just to clarify about the clogged drain. The catch pan overflows, water spills onto the top of the headliner, and runs down the pillars between the frame and covers, where it then often follows wires to the plugs and junctions. I have heard of lots of people having these kind of gremlins and traced it back to a sunroof leak, not necessarily on the Commander, but lots of other Mopar vehicles with sunroofs of this era.