2009 Mitsubishi Eclipse battery being drained

JRHUNT

MEMBER
2009 MITSUBISHI ECLIPSE
105,000 MILES

Left the key in on position overnight, next morn battery was dead, jumped car with another vehicle, it cranked immediately. Was fine all day, but dead next morn. Jumped again, started fine, went to mechanic to test battery who determined battery was fine, but said it was something electrical causing battery to drain. He said there was a reset somewhere on the car. Car has given no problems until key was left on overnight, so something in the electrical has to be malfunctioning. Please help, I absolutely cannot afford a mechanic. This car is not mine it is a friends letting me use it.

1 Reply

WRENCHTECH

MECHANIC
20,758 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 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.