Unusual electrical problem

[Rockster]

I have an unusual problem with my Z4.

Last week when I was driving the stereo cut out (no sound) and then when I stopped and restarted the car the radio display was lit up in amber but blank. In addition, there was no audio to the speakers.

I checked the fuses in the box, the back of the radio and at the amp which were fine. Since I had an original 2003 battery, I decided to replace it even though it tested ok as did the alternator. Wanted to rule that out. It didn't solve the issue.

In addition, I noticed yesterday that when I put the top down it seems to fall quickly the last 5-6 inches and doesn't stow as flush as it did. Maybe about a inch off from where it was so it seems the latch motors might now be doing what they should.

Every other switch, blinker, lock and function I can find seems to be working aside from these two things.

So there is an electrical issue of some sort. Any ideas or tips for troubleshooting?

Thanks!
R

[Finnegan]

How old is the battery? 9 out of 10 times weird electrical issues seem to be traceable to an old battery.

[Rockster]

I replaced the battery after I validated the fuses several days ago. The battery was my concern as well since it was 8 years old...even though it tested ok.

[3002 tii]

Originally Posted by Finnegan

How old is the battery? 9 out of 10 times weird electrical issues seem to be traceable to an old battery.

I was just thinking about this the other day, how long does the oem battery typically last assuming it gets regular usage? 6yrs?

[Rockster]

My battery had a 2003 manufacturer date and as I said, it tested fine so I think they last pretty long. I didn't need to replace it, but I was afraid of not doing it because I had read so many odd electrical stories when they start failing.

[Finnegan]

Originally Posted by Dubbedown

I was just thinking about this the other day, how long does the oem battery typically last assuming it gets regular usage? 6yrs?

I really don't know. There doesn't seem to be a hard and fast rule from what I've seen. Even with frequent usage the amount of miles driven, (short vs. long distances), temps encountered (winter/summer), all seem to factor in.

[Finnegan]

Guess you answered the "how old is the battery thing in the OP", sorry.

The radio and the top could be separate issues. The soft top is well known for having motor issues if the drains clog and it gets wet. Other issues can occur as well. Here's something to get started, lots on the top/motor here outside of that too.

Don't have a clue on the radio. Do you have access to an extended scanning tool (Bavarian Technique, P.A. Soft, etc.)? These would provide a view into module status and other things that could be used to help track down the issue.

[Rockster]

Fin - thanks.

I think the issue with the soft top has to do with the electrical motors that latch it down. Seems like a low voltage thing and I was hoping a common control or "thing" connected them since

The main motor itself works without issue and the top goes up and down...it just doesn't latch enough at the end. The top down light goes off and the car acts as if it stowed as it should.

I think you are right, I should bring it in to a dealer or mechanic who can diagnose the codes or plug-in.

[Finnegan]

^Dealer, or better yet a good indie shop (cheaper and probably often better knowledge of "weird" things, BMW techs tend to take a paint by numbers approach).