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Parasitic Drain Testing with a Twist

We see a lot of posters that have parasitic drains that mechanics cannot find. Some are simple; Cheap aftermarket radios, car alarms or remote starters. Some are much harder to find.

I found this YouTube channel a while back and I like this guy’s approach to diagnosis of the causes of problems. I watched him use an orderly, step-by-step, sequence to find the most unlikely cause for a huge parasitic drain in a Hyundai Genesis. Skip to the end if you want the cause but it is entertaining to watch him find it.

Post below your thoughts as to how it happened and why the “cause” even exists!

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That’s my favorite you tube channel.

I usually refer this site, https://www.popularmechanics.com/cars/car-technology/a5859/how-to-stop-car-battery-drains/ Best watch of the day, incredib;e!

The South Main guy is a great diagnostician, but…
I would have first monitored the drain while pulling fuses one by one.
Would have saved some time over using the heat camera or pulling connectors.

Any thoughts on WHY that blank fuse position had terminals at all? Or why someone placed a fuse in that slot?

I thought the FLIR camera was clever, myself. A lot of his videos start with… another shop sent me this car because they couldn’t figure it out… He seems to be the go-to mechanic for electrical problems as a lot of his videos contain that subject.

I’m disappointed he didn’t dig further to figure out what option that fuse is for. If I was to hazard a guess, that is a test port for manufacturing to force some points to be powered up early in the assembly process or just to make it convenient for production versus using the key.

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I agree! I think that is a manufacturing test port, too, to wake up the controls for an in-line test.

Not sure how he could find out what it is if it wasn’t in his wiring diagram.

I’d further guess that maybe someone decided to put their spare 10 A fuse into the unmarked slot.

Yeah, he may have never figured out the answer but he seemed to just accept it and (at least in the video) didn’t make any effort to dig further. I would have at least looked in the service manual or drilled around on-line due to curiosity. I don’t blame him for not looking further, just disappointed we didn’t get the “final answer” :slight_smile:

You’d think as long as they were silkscreening the cover, they would put “do not populate”, “no fuse” or some such verbiage in the legend.

I agree, somebody thought- what a great spot for my spare, how convenient!

Thanks for the morning entertainment. It was fun to watch and speculate.

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