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How to test for parasitic draw with a battery in the trunk?
I have a parasitic draw somewhere in my vehicle that I have been ignoring for quite some time now. I disconnect my battery after each drive cycle, and the other day when I was driving, my high beams went out, the symbol doesn't even flash on the dash when I try to turn them on. I have to find this problem.
I think the 'easiest' way to do this is to to test for amperage draw by connecting the multimeter and pulling fuses, but that would mean I'd have to pull a fuse, run to my trunk to see if the values change, run back to the engine bay, replace the fuse & repeat. And that's not even taking into account how I'm going to check the fuses in the cabin area, there is no way I can depress the cabin light actuator inside the door assembly without having someone physically do it themselves.
Is there a easier, more practical way of doing this whilst having a battery in the trunk? I have a cheap multimeter and a test light that can test for ground.
Jumper wires to get the dvom up front. With that said you have to have trunk closed,door latches closed and wait for modules to shutdown(some vehicles have hood switches as well so may need hood latch closed as well), also some fuses will wake up modules when reinstalled so don't fall for the I got the right circuit the first time you see a draw come across when reinserting a fuse
Any speaker wire or or other wire laying around would work as a jumper wire. if none is available you can latch the trunk switch and go back and forth to dvom. Some have main lead come from battery positive to lug at underhood fuse box you may be able to disconnect it there to hook up dvom but I didnt catch what year make and model you were working on
What is a dvom? I'm not sure if my speaker wires are live/working, as I bought the vehicle without a working radio, and haven't yet installed a new radio. My floodlights are also non operational. Several faulty electrical issues.
A number of ways of doing but it sounds like you have a fairly large current draw, if you are using a MultiMeter (DVOM) you could very easily blow the internal 10 amp fuse in the meter. If I suspect a large parasitic draw I usually start by disconnecting the alternator and screen wiper
Post on similar issue
" We're trying to plug a hole in the universe, what are you doing ?. "
(Walter Bishop Fringe TV show)
Look up parasitic draw on you tube. You can find it by doing voltage drop test at the fuses. There are some good videos on you tube. And I have been successful doing this several times.
Also you can use your volt meter set to amps and connect it between negative post and negative cable.
But best way I have found is to do voltage drop test across fuse. There is a chart out on the net that tells you how big the draw is based on your results. Once you find the circuit. Get a wireing diagram for it and trace it down that way.
