My batteries keep dying. The batteries are a couple of years old (Interstate Megatron). They seem to hold a charge reasonably well... though I should probably go get them load tested. The terminals and clamps are all clean and making good connections.

I've checked the current draw with the truck off and no accessories on. I measure something like 200mA. From what I've read, the acceptable threshold is around 50mA (is that right?).

I went through and pulled fuses one by one to see if I could find an offending circuit and didn't come up with much. The biggest offender was Fuse 19, but the current only dropped to 120mA. Occasionally, when the truck first starts, the radio and windows seem like they aren't getting any power. This happens rarely and usually resolves itself in a minute or two of running. Might just be a strange electrical gremlin or another clue/symptom of the same problem.

My truck is rusting to pieces underneath -- its pretty sad under there. I suspect that there are some dirty connections underneath that are perhaps causing the issue. Does anyone have any experience or suggestions on where to start looking next?

 

I traced a parasitic drain to my factory radio. I pulled the radio. There's been a big empty hole there in the dash for years now. But the emptiness did eliminate the parasitic drain.

 

I have an aftermarket radio installed. I'll try pulling it specifically though to see if it makes any difference. If it was the radio, I think that I would have seen a current difference when I pulled the radio fuse from the fuse box.

 

How long have you had the problem? Is your alternator warm when sitting?

 

It's a relatively recent problem -- maybe the past 6 months or so. The alternator is not warm when the truck is sitting.

 

Those things can be tough and I've been through two of them. One problem that I had was that I had an amp meter that was not accurate. What I ended up doing was taking pictures of the fuse boxes and checking the amp draw. I pulled every fuse and verified that I was at zero draw and inserted the fuses one by one checking the draw along the way. If anyone has a better way, I'd love to hear it.

 

Alternatively, while all the fuses are out you can test each fuse slot in the box, one at a time and see who the culprit is.

 

I like the suggestions. Sounds tedious... but not sure that there is another way around it. I spotted these little guys: that seem like they might make the job a bit easier. I might be able to make some of these out of old blown out fuses.

 

Those look interesting. Of course you have to have your body in the worst of positions to try and test them.