Battery drain

[Jacobh93]

Having a battery drain issue on my wife's 03 Expy. If it sits for more than a day, it won't start and needs a charge. Found out its drawing .6 amps when off, and I've narrowed that down to fuse 5 (PCM KA power, sV deactivate switch, manual climate control mode switch, stop lamp switch, brake shift interlock solenoid, EATC control head, BSM module, speed control servo, 3rd row seat relay) drawing .4 amps and fuse 21 (instrument cluster, interior lamps, electronic park brake relay, TPMS (don't have tpms I don't think).

Basically, I have no idea from here on. Which of those could be drawing when it's off? How do I narrow it from there? Is it normally just a short somewhere and I have to locate it? Are there fuse specific wiring diagrams somewhere that I could find?

Any help is appreciated.

 

[stamp11127]

Same way you found the circuit. You have to remove one load at a time, in other words isolate each branch circuit. Keep in mind you may have more than one circuit pulling current.

 

[Hamfisted]

Pull the bulb out of the glove box courtesy light and see if your load drops to .07-.06 amps max. I had a problem with the switch on the glove box on my '03 and the glove box light was stuck on. Same results you're seeing. If you find that to be the problem you can replace the switch, or just leave the bulb out, or unplug the switch power supply behind the glove box. The glove box light is part of the interior courtesy lights on fuse 21. How old is your battery too? I assume you're using a digital multimeter amp gauge for your test? You're running the amp meter between your battery's ground cable and negative post right?



-Mike

 

[Jacobh93]

Pull the bulb out of the glove box courtesy light and see if your load drops to .07-.06 amps max. I had a problem with the switch on the glove box on my '03 and the glove box light was stuck on. Same results you're seeing. If you find that to be the problem you can replace the switch, or just leave the bulb out, or unplug the switch power supply behind the glove box. The glove box light is part of the interior courtesy lights on fuse 21. How old is your battery too? I assume you're using a digital multimeter amp gauge for your test? You're running the amp meter between your battery's ground cable and negative post right?



-Mike

Yes, it was a new battery. I did check that bulb, and the one under the hood. The problem was actually a door ajar sensor. I knew it wasn't working, so I was turning off the cabin lights manually. Apparently, even with those lights off, it's pulling power if it thinks the door is ajar. Sprayed WD40 into the latches, and that fixed it. dropped to .03-.04 amps.

Thanks for the replies!

 

[palmerino89]

Back wiper blade is a common problem. It goes off track and pulls power even when the truck is off. If it happens again, open the rear window and look at where the wiper locks in. It may have reset itself when you were hitting everything with wd40.

 

[poppadon56]

I have an 08 - Limited EL and the battery has been giving me issues for a couple of years. I have brought it to my Ford dealership at least 4 times and they can't find any problem. They said they did disconnect the rear wiper and the power running boards because they weren't working properly. And the problem still exists. Latest was on Monday, I started the truck up with no problems, drove a couple of miles to store and when I come out it didn't start. Got a boost and have been Ok since.

To my question, is .03-.04 amps a normal drain for this vehicle when I think everything is off? I would have thought my many trips to service would have discovered something.

Thanks,

Don

 

[stamp11127]

You should start a new thread for your problem. Once you have done that I will remove these posts and we will go from there.