I have a parasitic battery drain problem. I placed a multimeter in series between the negative post and the negative cable. The meter showed 12.5. I pulled every fuse in the car and still the meter showed 12.5 (sometimes higher). Now what can I check?
by 
Alfista
ANSWERS: 5
-
I'll assume the meter was set for amperage. If that's 12.5 amps, there is a huge draw. It seems more logical that it is 12.5 milli-amps which would be acceptable in terms of drain. If in fact it is 12.5 amps, look for something that has a fusible link and not a "blade" style fuse, such as the alternator, starter solenoid... 12.5 amps would be a HUGE draw!! How long does it take for the battery to drain?
-
I apologize if this doesn't apply, but I offer this as I have done it myself by accident. When you switch over the multimeter to DC current, did you remember to shift the red lead from the voltage input to the current input? On mine, if you don't, it actually displays voltage still, even though it is on the current range. 12.5A is suspiciously like 12.5V, that's all...
-
Forget the tests and pull the radio fuse. Drive normally for awhile to see if battery remains charged. Have had no problems since replacing the radio.
-
Do you hear a clicking sound when you remove and reinstall the negative (-) battery cable? If you do remove each relay until you don't hear the click anymore. Then you will know what circuit is problematic and can troubleshoot it if its a system you don't need to drive the vehicle, leave the relay out and the circuit will be disconnected from the battery system.
-
Strip it! Take All Wiring off of the + Terminal & don't allow them to touch each other or ground. Now go between the (+) Battery Terminal & each wire to see which one is "Drawing Current". When one shows "Current Draw", follow it out & start "Pulling Devices" in that circuit until it goes away. After Market Radios & Amps are a common problem as are bad "Blocking Diodes" in the "Regulator Circuit" of the Alternator!!! John
RELATED QUESTIONS
Copyright 2023, Wired Ivy, LLC