Battery drain

TROY MCCREA

MEMBER
1996 FORD MUSTANG
3.8L
V6
RWD
AUTOMATIC
189,000 MILES

I have been at this about four hours now I have unplugged the connectors at the passenger side of the engine compartment, I have unplugged the ECM, the radio control module underneath the console the airbag relay underneath the dash next to the fuse panel. I have about a 12.81 amp draw and all of those things made no change until I unplugged the wire connector in the driver side wheel well leading inside the car. Attempting to play electrician I think I have narrowed it down to one pin that is causing my amp draw, but I cannot seem to find any diagrams that will tell me what circuit that one pin it is a black wire with a purple stripe and an orange stripe. Any information on this would be greatly helpful.

1 Reply

WRENCHTECH

MECHANIC
20,757 POSTS

There is a procedure for finding a battery draw like that.

You will need a digital ammeter and a jumper wire with clips on the ends to do this.
First rig any door switches so you can have a door open without triggering the interior lights and unplug the hood light. Remove one battery cable and attach the meter in series between the battery cable and battery post. Take the jumper wire and also attach it the same way. Leave the jumper wire on for at least ten minutes to expire all the automatic timers. Now remove the jumper wire and read the meter. Anything over 50 amps is too much draw. The way you locate this is to start removing fuses one at a time until the meter drops to normal level. This will be the circuit with something staying on. Determine what components are part of that circuit and check them individually until the problem is isolated.