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Hunting down a parasitic draw, is this the right way to do it? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

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YOUR RESEARCHHunting down a parasitic draw, is this the right way to do it? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Leading reported evidence

Set multimeter

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Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

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Suggestion

And when you pick it up again, be sure to set your multimeter to measure current (Amp scale) rather than resistance.

Hunting down a parasitic draw, is this the right way to do it? - 986 Forum - The Community for Porsche Boxster & Cayman Owners
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Leading evidence: 'Set multimeter' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Set multimeter' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.

Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.

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1 matching discussions · 14 captured posts examined · 0 partial discussions

Compare 3 other evidence results

Test amp load

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

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.

Hunting down a parasitic draw, is this the right way to do it? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Test parasitic draw

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

This morning I attempted to test for a parasitic draw, but I'm not sure if I have the multimeter set up right?

Hunting down a parasitic draw, is this the right way to do it? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Use (also indicating the a)

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context

Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.

Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

You already found out about the terminal to use (also indicating the A).

Hunting down a parasitic draw, is this the right way to do it? - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Frequently discussed actions (4)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Set multimeter

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

And when you pick it up again, be sure to set your multimeter to measure current (Amp scale) rather than resistance.

Hunting down a parasitic draw, is this the right way to do it? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Test amp load

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

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.

Hunting down a parasitic draw, is this the right way to do it? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Test parasitic draw

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion · Original poster

This morning I attempted to test for a parasitic draw, but I'm not sure if I have the multimeter set up right?

Hunting down a parasitic draw, is this the right way to do it? - 986 Forum - The Community for Porsche Boxster & Cayman Owners

Use (also indicating the a)

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1

0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.

0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.

Suggestion

You already found out about the terminal to use (also indicating the A).

Hunting down a parasitic draw, is this the right way to do it? - 986 Forum - The Community for Porsche Boxster & Cayman Owners
Coverage and how to read this overview

Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.

14 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

  • 986Forum: 1 discussions

0 evidence records excluded for query context · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.

0 acknowledgements have no verified action link; they do not establish a repair result.

Generation: 20261026T183130Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

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!

POST 2Original post

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.

POST 3 / ORIGINAL POSTEROriginal post

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.

POST 4Original post

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

POST 5Original post

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?

POST 6Original post

Quotes source post: 665678

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.

POST 7 / ORIGINAL POSTEROriginal post

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!

POST 8 / ORIGINAL POSTEROriginal post

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. ��

POST 9Original post

Quotes source post: 665684

That would be JFP. See above (or below).

POST 10Original post

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).

POST 11 / ORIGINAL POSTEROriginal post

Quotes source post: 665692

Yes! Thank you so much for your help!

POST 12 / ORIGINAL POSTEROriginal post

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 .

POST 13Original post

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

POST 14Original post

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

This is a source reference. Confirm exact model applicability in the original material.