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1995 Audi A4 Repair Question


Topics covered: Battery, Battery cable, Door.
Mileage: 10,900 miles.

Asked on April 16, 2012

Battery keeps going flat

Battery goes flat after about 2 days, had battery and alternate checked both ok. alternate ok when benched tested but only puts out about 10amps when on car.
Avatar Asked by dennis briggs

Answer

Replied on April 16, 2012

You may have a parasitic draw on the system.
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.

Tiny Answered by Wrenchtech (expert)
14,743 answers provided
Replied on April 16, 2012

thanking you for a very imformative answer

Tiny Response from dennis briggs
1 question asked