E30 current drain in fuse# 17

[ecsk]

A few months ago, the E30 started having battery flat after 4 days of not driving, I did a current draw test, it shows about 100mA draw which is too high although not extremely high, then did a fuse pull isolation, turn out when I pull fuse# 17, current draw drop to 30mA.

Fuse# 17 is sunroof and power windows, both of them are working fine.

Anyone has idea on where do I trace further, or had similar experience that can share :)

[george graves]

The only thing I can think of at the moment is the sunroof relay. Does your sunroof work as it should? Reason I ask, is if that relay was latched or messed up somehow, that could draw power easily.

Are your switches lighted when the key is out/off?

[george graves]

The only thing I can think of at the moment is the sunroof relay. Does your sunroof work as it should? Reason I ask, is if that relay was latched or messed up somehow, that could draw power easily. (the relay is located next to the sunroof motor, under the cover)

Are your switches lighted when the key is out/off?

[ecsk]

George, thanks.
Sunroof is working fine as how it should, all switches light are off when key is out.
I'm not aware there is a separate sunroof relay until you say so :) how to determine if it's playing up ?

[george graves]

Unplug it and see if the draw goes away. You have to remove your visors, and mirror. and some sunroof screws.

[Das Delfin]

might try unplugging the sunroof motor itself as well. If it's easier (I have a cabrio so..you know)

[ecsk]

Look like a fair bit of effort to access the sunroof motor or relay.

You'll love youtube.
I'll follow this https://www.youtube.com/watch?v=Xd6-Ps1lXPs to drop the front headliner cover this weekend.

[george graves]

I'd have to look at the diagram, but unplugging the switch might show a drop in the current draw, then you would know you need to get in there.

[ecsk]

Now it is interesting, unplugged sunroof switch, no change in current draw.
pop up the power windows circuit breaker which suppose to cut power to both side window motor, still no change.
I noticed when I press down or pop up the circuit breaker, current draw goes up to 220mA for a few second, then drop back to 90-100mA.

I don't know what to do now :(

[george graves]

What "circuit breaker" type do you have? There are two types.

The ones with red around the edges - when it's presses and out, you can see red. It also has a screw on the back, and is an actual circuit breaker with a bi-metallic strip, That's there for a bone head situation if you were to say, leave a really heavy package resting on the switch, it'll heat up and cut power, so that the window motor isn't running. It will heat up, and cut power saving your motor, and a over heating of the wires and motor. But it will then cool down and cycle over and over. Kinda worthless IMHO. Don't leave a huge package on your console - but BMW must have had to do it as a safety feature.

The other type is an even more of a useless - it's just window switch lock out. No breaker, nothing it's literally just a switch. And there are no red on the switch edges at all. Early e30's didn't have them, and IIRC euro cars didn't have them, may have been a US DOT mandate.

Next thing I would check is to remove the "circuit breaker" and replace it with some wire, and check the current.

Hope that helps.

[ecsk]

I have been having fun with E30 electric :)
I've almost checked every possibility from fuse#17 to cause drain but still no luck, then recheck every fuse, fuse#17 has no drain !!!!! Now found fuse#21 is causing drain !!
Eventually I isolated its the blue plug (C1) behind the cluster that cause problem, when I unplugged it, current draw is 20mA.
Question is, do I need to replace the SI board or just the SI board battery ? SI reminder light has not been working since I own this car, when the car is started, the 5 green SI light does turn on for a couple of second though.
If SI board battery is dead, would it cause current drain, I've seen opposite opinion about this on a few BMW forum.

[george graves]

Doh! Yea, the Si board can cause batty drain. This guy is an expert on it (I am not so much as he is)

http://www.r3vlimited.com/board/member.php?u=40393

[george graves]

Doh! Yea, the Si board can cause batty drain. This guy is an expert on it (I am not so much as he is)

http://www.r3vlimited.com/board/member.php?u=40393

[Das Delfin]

Those green lights are acting as they should. They should light up when your key is ON but the car hasn't been started. Then go off once the motor is running