Parasitic battery draw

Aidynl

Member
Joined
May 19, 2021
Messages
28
Location
Kelowna
Hello, I have 2003 jeep tj Rubicon 4.0
Battery has been dying very fast.
I've tested the cells of the battery and its full charged voltage and that was good
Tested the charging when running and that seemed good
Today tested the current draw off the battery it was high (7.72A) Maybe I wasn't doing it right though *Photos below*
Well testing the current I pulled the fuses behind the glove box as well as the Blade Fuses (Didn't touch the relays and the other fuses) in the engine bay and there was no drop in current also disconnected my amp from the battery and didn't see no drop either.
Any advice or more things to test would be greatly appreciated thank you all very much.

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That’s the right way to check for a draw, but touch the cable to the post for about 30 seconds the disconnect while leaving the meter leads connected. This will allow timers to shut off such as the dome lamp. From there disconnect fuses then relays. Disconnect the alternator also. This should isolate the circuit. You may also have a couple fuse links at the positive terminal of the pdc.
 
Pull one fuse at a time and see if you can spot the circuit that’s drawing the current. After you pull the fuse and don’t see a current draw replace it so you don’t lose track. Of course do this while you have the meter in series like you’ve got it.
 
thanks for all the help but still stuck, here the list of things I did.
-Took every fuse and relay out of the engine bay
-Disconnected alternator wire from battery
-Completely ripped out after market alarm system
-Took of Powered rear view mirror
-Added switches for stereo and Amp

Only thing that made the current drop was disconnecting the whole fuse box haha.

Still had no change to the current reading so still very lost but on the bright side I now don't have to deal with the aftermarket alarm system.
Any other ideas? at this point thinking of just wiring a switch to the battery.
Thanks guys
 
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Did you disconnect the large power wire from the Alternator or just the small plug? I would open the back of the pdc and look wor out of place wires or bare wires.
 
Also, do you zero out the meter before reading your measurements?

I have that same clamp, and I have to press and hold the orange "SEL" button for a few seconds to calibrate it. Otherwise, it will normally read 1-2 amps with nothing connected.
 
Did you disconnect the large power wire from the Alternator or just the small plug? I would open the back of the pdc and look wor out of place wires or bare wires.
Yes disconnected the power wire from the alternator, Should my alternator wire being going to my fuse box or my battery post?
 
Also, do you zero out the meter before reading your measurements?

I have that same clamp, and I have to press and hold the orange "SEL" button for a few seconds to calibrate it. Otherwise, it will normally read 1-2 amps with nothing connected.
Yes I made sure it was zero before.
 
Aside from your draw problem-—- how old is your battery? I replace mine at 3-4 years old just so I don't have a failure on the trail.
Also get all the battery wire strands inside the terminal clamp.
 
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Hey ! Let me throw in my 2 cents, make sure everything is powered down before looking at draw. Your doing test right. Did you load test battery ?? What was voltage before and after load test ?? How old is that battery ???
 
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Think it is fuse 27 anyone know what this controls ? Was looking but cannot find it
Also just noticed when I connected my amp to my battery and my ASD fuse (9) it goes back up to 7 amps. fuse 10 hd/lp does a 3 amp draw and ignition makes it go up to 7 amps too
 
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Factory service manual is here to download in the reference section. If it's like a 2004 it could be the rear window defogger, reverse lights or the transmission range sensor? I think it's called fuse 7 even thought it's in slot 27. Section 8W-11-6 in the wiring diagram on mine.
 
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Seems that multiple fuses are drawing power but weirdly they all pull 7amps can’t figure out what it is so a battery disconnect is probably going to be the plan thanks for help guys I appreciate it a lot.