Weird Battery Drain - All fuses out

[hellspcangel911]

I scanned it with BMW Scanner 1.4, there was nothing out of the ordinary.
The AUX fan was unplugged, no change in draw.
Since all of the fuses in those three locations I ruled out it being a map light or an accessory. It's got to be either a relay somewhere (suggestions where to look?) Or perhaps some idiot installer took power from the unfused cable to install a Lo-Jack type of hidden system. I don't think the car has one but you never know and any other type of installation would have been spliced somewhere convenient.

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[hellspcangel911]

I did, one by one checking after each one was pulled till they were all out and I still have a drain.

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[jfoj]

Hopefully you are not using an inductive DC Amp probe. These are notoriously flaky and hard to zero out. Below 10 Amps I prefer to use a straight DC Ampmeter or the 10 Amp scale on a mulitmeter rather than any inductive DC clamps.

The problem could be a bad diode in the alternator that is partially shorted. Have you disconnected/checked the drop to the alternator?

Not sure if you have BMW Assist, I know that GM had big problems with their OnStar units draining the batteries. I assume if you have BMW assist then the fuse has been pulled.

[hellspcangel911]

Jfoj, thanks for the response. I don't have BMW assist but yes the duse is pulled. I'm using a digital amp meter set to 10amps because the draw is still to high for the milliamp scale. It's connected in series between the ground post on the battery and the terminal connector.
I'm pulling relays under the hood now...fingers crossed
As for the alternator, I thought disconnecting this would separate the alternator?

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[hellspcangel911]

Ok all relays under the hood in the sealed compartment removed, no change in draw.
I'm out of ideas


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[upallnight]

Did you look at the e-box by the front cowl on the right side of the car (passenger side). If you have Bentlet it is page ECL-17.

There's is also an unloader relay called Terminal 15. You can check it by removing a connector to one of the coil over plug ignition coil and checking for current at the connector terminal. If you have 12V that is the relay that is sticking. See page ECL-19 Bentley Manual.

[hellspcangel911]

I pulled all the relays out of the e-box up front and no change. I have 0volts at the ignitors

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[hellspcangel911]

You are correct, that cable is a Y going from the post to the starter and alternator.

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[hellspcangel911]

Well, good news, kind of. Turns out the multimeter was broken. I lent it to my neighbor last week who was diagnosing his generator..... Hmmm.
Anyway, it read 3amps with the probes disconnected. I didn't try that before because I didn't want to wake the car up and start over.
Long story, got another one. Confirmed it works, put ALL the fuses and everything back in, took the jumper cable off after it went to sleep and I have 34mA
Not sure what to do with this information, whole day wasted and nothing to show for it.
I checked the alternator, put in a new Interstate battery but still had this problem so I'm sure there's a drain. I guess I'll.be doing this test again later on.
Thanks k you to all those that replied, you helped me push thru it.

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[hellspcangel911]

So I checked the draw with the car asleep between the positive connector for the starter and alternator...


Alternator has 8k miles on it and less than a year, going to try and get it swapped out under warranty

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