ATTN: BMW Techs...Another Q

[StereoInstaller1]

OK, guys, I need more help.

I have a 1998 540i coming in tomorrow. Customer says it is a battery drain issue. I cannot find any aftermarket anything, except the Sirius radio...but when it is disconnected, same issues occur. About a 1.7A draw with the entire car shut down.

The only oddity I can find is that the gear indicator in the center console stays lit after the key is off...but it will shut off after about 3 hours or so.

Any suggestions?

Thanks!
Luke

[Ben Carufel]

Check the trunk light.

[PiercedE30]

check any lights that are time delayed

[RL 325i]

Luke,

I do have a 1998 540i6. Althought I don't have battery drain problem right now, One of the common failure in these car is the FSU. When this FSU failed, your heating control will go crazy. Fan speed may be full blast by itself or lost control of the fan speed. Others owners claimed that it will also create battery drain.

I will disconnect the FSU, then measure if there is anymore drain. If no more, you found the problem. Replace the FSU.

Below is the link on how to replace the FSU.

http://www.540i6.com/finalstagereplacement.html

Thank you for helping me in the past about alarm wiring code in the past:up: . Hoped it helps

Ron

[trent]

OK, guys, I need more help.

I have a 1998 540i coming in tomorrow. Customer says it is a battery drain issue. I cannot find any aftermarket anything, except the Sirius radio...but when it is disconnected, same issues occur. About a 1.7A draw with the entire car shut down.

The only oddity I can find is that the gear indicator in the center console stays lit after the key is off...but it will shut off after about 3 hours or so.

Any suggestions?

Thanks!
Luke

Keep a meter hooked up, pull fuses till you find circuit. Check circuit.

[AndrewBird]

^^^ What he said.

[AdamF 88iS]

Keep a meter hooked up, pull fuses till you find circuit. Check circuit.

Ditto this.

FSU won't do it.

[dirty30]

Yep. Draw needs power 12v+, Power needs fuse, take away fuse... no more draw.

[markseven]

OK, guys, I need more help.

I have a 1998 540i coming in tomorrow. Customer says it is a battery drain issue. I cannot find any aftermarket anything, except the Sirius radio...but when it is disconnected, same issues occur. About a 1.7A draw with the entire car shut down.

The only oddity I can find is that the gear indicator in the center console stays lit after the key is off...but it will shut off after about 3 hours or so.

Any suggestions?

Thanks!
Luke

Luke, it's supposed to shut off after 15 minutes. 3 hours is obviously waaay too long.

[StereoInstaller1]

Hey guys, I already know how to test for load.

I am looking for known issues.

Thanks for all the input though!

Luke

[AdamF 88iS]

I don't think there are any known issues for this. You may have a stuck seat switch, stuck trunk latch button or lock actuator, or some light left on. Those are things I've encountered on various BMWs that have caused quick battery drains.

Other than that you could have a bad module somewhere that is powering something it shouldn't.

Ignition switches on those cars do fail; but that usually results in the ACC circuit never getting power so things like horn and radio will quit on you. I've never seen one fail so that it gets stuck on.

[e30grip]

check final stage unit for blower motor and aux fan for a/c.

[StereoInstaller1]

Well, guys, did the fuse check. Trusty Fluke said 1.2A draw. Pulled fuse after fuse after fuse...never found one that made a difference. Main power to the fuse block dropped it to .025, which is cool...but everything in the car was dead. I bet it is just like someone suggested, something (motor, relay, solenoid) stuck open.

I did find about a .26A draw in the amplifier...so I used a relay to make a switched power circuit...Cheezy work, but it helped.

This is a repo car. I do a bunch of work for thier (Northwest Community Credit Union) repo manger. It has been sold and is delivered...with a .82A draw. WAY too much of a draw IMHO, but we will see. I told him I didn't like it (Mr. Repo Manager) but he said ship it, and they can bring it back if and when I have more time.

I am just gonna hope for the best.

Luke