There is a spark when disconnecting the ground.

ANONYMOUS

MEMBER
2005 TOYOTA 4RUNNER
67,000 MILES

There is a spark when disconnecting the ground wire from the battery of my 2005 4Runner. All lights and switches are off when I disconnect the battery, yet it still sparks as though there were a draw of current from the battery. I am replacing the battery because it would not hold a good charge, so the spark seems to indicate there is a short somewhere that is drawing current when no switches or systems are turned on. Any ideas? Thank you. Denver

1 Reply

WRENCHTECH

MECHANIC
20,761 POSTS

You can't check anything that way as the car has numerous timers that will trigger the the battery is disconnected.

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 10 minutes to expire all the automatic timers. Now remove the jumper wire and read the meter. Anything over 50ma 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.