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Electrical Problematic Quagmire

I’m currently having electrical trouble with my 2005 Dodge Durango SLT.
Something is currently draining the battery overnight until the battery is completely dead.
My family and I checked some of the fuses for the Audio System and the alternator as well; neither being the culprit robbing the battery of its power. What should be the next area my family and I should check to solve this problem. Feel free to ask questions, and I’ll answer them to the best of my abilities.

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The first step is to check the health of the battery and its connections.

The battery and the connections are good. But thank you for the reply.

What procedure did you use to check those two circuits?

Checked the alternator with the car on and off with a DVM. Removed the entire radio/nav system

Hope this helps

Check the under hood light and the glove box light if there is one.

As soon as you open either, touch the bulb. it should be cool yet. If the bulb is hot the switch is not shutting off that light. Also check that you didn’t mistakenly turn on the cargo lamp, located on the rear top of the cab.


I’m curious why you removed the radio and nav system.
Anyway a DVM wont tell you necessarily whether the battery is good. You really need to do a load test.
The Auto parts store can usually do that for you for free. If your battery tests out to be good then follow the instructions in the link sent by “Barkydog”
I’m more of a video guy so here is a link that shows the procedure.

If you suspect a battery drain, you need to hook up a test light to the battery. Note how bright the light is and start pulling fuses one by one and replacing them. When you find a fuse that dims the light considerably, that is the circuit that the problem is likely in. Or you can have a shop do it if you don’t have schematics, a test light, or a little knowledge.

A word of caution though, it can be intermittent. I have had two situations where one was the door switch that turned on the interior lights. Due to rust it would go on in the middle of the night. The only way I found it was going out to the garage one night and seeing the interior lights on. The other was with the Electronic Level Control that turned on the pump to level the car. It was shorted out but only once in a while. Again found it by chance laying under the car. Good luck. Carry a jump pack in the mean time.

I had a 2002 Chrysler minivan that would drain the battery overnight, It turned out to be a faulty fan controller turning on the radiator fans hours after the car was shut off.

Not sure what method you used to rule out the alternator out of the equation here… What test did you put it through? Making proper voltage is not the test to prove it out.

Charge the battery (assuming your batt is healthy) and disconnect the hot wire to the alternator…see what you get the next day… If it starts up no problem, you found the problem.

When you reconnect the hot wire to the alternator if you get a rather big spark when the wire touches the lug…that is a clue its pulling voltage. Also…if you feel the temp of the alternator when the engine is cold…if its warm…you found the problem.

Just a couple things to look into…beyond the obvious ones like something staying on when it shouldnt be on.

If your alternator has a bad diode, your battery can drain . The bad alternator diode can cause the circuit to charge even when the engine is shut off, and you end up in the morning with a car that won’t start.