nathandcasey

He everyone,
I purchased the truck back in 08 and it has had a drain on the batter pretty much since I've had it. The guy who owned it before me had a xm radio installed as well as an aftermarket hands-free cell phone deal. I've disconnected both thinking these were the causes of the drain, but it didn't help. I found out how to diagnose a parasitic draw and I hooked my multimeter up to the negative battery terminal and the ground wire. I set the multimeter to 10A and 200m. I get the same reading for both. It starts with a 1.5 amp draw during the "wakeup process" and drops to .03 on the reading and stays there. I'm confused, because this does not seem like it is enough of a draw to drain the battery. I've attached a picture of the multimeter setting and reading. Maybe I'm doing something wrong? I hope I've given you enough to go off of. Thanks!

Nathan

River1

Since no one with more information then I can offer has replied I'll try. I don't understand what you wrote. What you described doesn't match what I knew of parasitic draw. I did a quick yahoo search and there is no shortage of information of the process. I suggest you check them out and start over.

I will help with posting another question you will need the answer to before you proceed.

nathandcasey

Hmm... Okay. Maybe I'll try rephrasing the question. I've researched what a parasitic draw is and found it to be a short in one of the electrical systems to draw power from the battery when the vehicle is turned off and should have little to no drain on the battery.

My problem is that my battery is being drained while in the off position and just sitting and I have gone through several batteries already well before the batteries should have been used up. I used my multimeter while the negative cable was unhooked to look for a draw on the battery and surprisingly, the number you see in the photo above is the the draw on the battery in the off position. I even left it connected for several hours to be sure it didn't change.., and it didn't.


So I guess my question is, what could be draining the battery if I am getting no significant draw on the batter? What else would cause it to drain?


I hope this helped. I'm not sure how else to ask.

River1

I don't know. "Back in the day," before all the computers and standby power, parasitic draw was found with a battery shunt and looking fuse by fuse.

I suppose you could pull a different fuse every night until you find where your battery isn't drained. Of course it will need to be a single system that's the problem.

nathandcasey

Yeah, I suppose you're right. I'll go down tomorrow and try the whole process again. There has to be something I'm missing. If the battery is being drained there is a draw from somewhere. I'll just have to keep looking. Thanks a lot for the input.

broncojunkie

Have you tried the hot side to see if there is a difference in your reading? There shouldn't be, but I think I'd have to check anyway just to see for myself. Since you're experiencing a battery drain issue, something has to be draining it. FWIW, ,I've got the same or similar problem in my 88 mustang. Showing minimal amount of drain when I test it on the meter, but it's still draining somehow. As long as I unhook the battery, it retains its charge.