Hunting down a parasitic draw, is this the right way to do it?

[BoxsterInTheSun]

The battery on my 2002 base 986 goes dead in around 5 days if it isn't driven.

I suspect it might be something to do with the double din radio I installed, although can't be sure as I did that install having not owned the car long enough to know if I caused the problem or not.

This morning I attempted to test for a parasitic draw, but I'm not sure if I have the multimeter set up right? I've included a picture below in the hopes someone can give me a bit of guidance.

My understanding is anything over 50 is not good, and mine is reading around 113.

If this setup is correct, my next step would be to start pulling fuses until I find the one that drops the number back down to something around 50.

Is that the right way to think about this?

Thanks in advance!

[JFP in PA]

You need to hook up the meter, then let the car sit closed up for 30-45 min before taking a reading; hit allows various modules to go to sleep before you can get an accurate reading.

And yes, 113 mA is way out of line, normal is 40-60 mA.

[BoxsterInTheSun]

Thanks so much. So connect everything as it is in the picture, but keep it that way with the meter ON for 30-45 minutes?, then take the reading?

When pulling fuses, do I need to repeat this wait time each time I pull a few and test?

Thank you again, I really appreciate it.

[JFP in PA]

Np, once the car is "asleep", pulling the correct fuse will drop the mA load showing on the meter.

[Gilles]

JFP, once the car is on 'sleep mode' if you open the door , would this 'wake up' the car, or this would only happen after you turn on the ignition again?

[JFP in PA]

Originally Posted by Gilles

JFP, once the car is on 'sleep mode' if you open the door , would this 'wake up' the car, or this would only happen after you turn on the ignition again?

Depending upon the year/model, if you leave the door open while waiting for the car to go to sleep, the interior lights should shut off and the car is sleeping with the door open. If the interior lights do not go off, the car will still be awake. You can also use something like a strong magnet to keep the door switch pressed down if it is one that stays awake.

Power Probe makes a new tool that is a draw monitor with a battery in it that plugs into the OBD II after which you disconnect the car's battery, and the tool is powering the car's systems and lets you see when it goes to sleep or awakens, which make the process that much simpler. They also have some adaptors for the multimeter probes that hold them in the perfect position to test the amp load on a fuse without pulling it.

[BoxsterInTheSun]

Thanks again JFP. I think I might have something setup incorrectly. The car is never "awake" with the way I have the wiring in the picture. I have to touch the negative terminal from the car to the battery to wake it up. As soon as I remove it the entire car is dead, no interior lights, alarm light flashing, nothing.

Any tips on what I might have wrong based on the picture I posted in my original post?

Thank you again!

[BoxsterInTheSun]

I think I might have figured it out...the red probe was plugged into the wrong port on the multimeter.

Plugging it in to the car right port on the multimeter makes the car "awake", but also makes it go nuts with a loud clicking/banging that's coming from the trunk area. It seems to stop if I put the key in the ignition and turn the ignition on ( without starting the car ).

I'm going to take a break from this until I get some advice from people much smarter than me. ��

[Starter986]

Originally Posted by BoxsterInTheSun

I think I might have figured it out...the red probe was plugged into the wrong port on the multimeter.

Plugging it in to the car right port on the multimeter makes the car "awake", but also makes it go nuts with a loud clicking/banging that's coming from the trunk area. It seems to stop if I put the key in the ignition and turn the ignition on ( without starting the car ).

I'm going to take a break from this until I get some advice from people much smarter than me. ��

That would be JFP.

See above (or below).

[Marc_986]

And when you pick it up again, be sure to set your multimeter to measure current (Amp scale) rather than resistance. That should help as well. You already found out about the terminal to use (also indicating the A).

[BoxsterInTheSun]

Originally Posted by Marc_986

And when you pick it up again, be sure to set your multimeter to measure current (Amp scale) rather than resistance. That should help as well. You already found out about the terminal to use (also indicating the A).

Yes! Thank you so much for your help!

[BoxsterInTheSun]

Just circling back. I think I found the problem.

I had installed a double din head unit a while back, and mistakenly powered the OEM amp from the following wire in the radio wiring harness:

Red/Black (thick) Constant power 12v (Fuse D8)

I've now moved it to this wire:

Orange 12 volt switched power (Fuse E1)

Fingers crossed that's the end of this issue. Thanks all for the amazing help here and the radio wiring chart found here.

[tcoradeschi]

I think it’s a safe bet that you found the culprit.

[wiebuschk]

FWIW my alternator was the drain on my battery. The rectifier diodes were leaking to ground.