Dead battery? on my new ZHP

[GregD]

I hadn't driven my car for 10 days. Yesterday, when I went to use it, first it didn't unlock with the remote, then I opened the door and none of the interior lights came on. Tried to start it anyway - nothing, not even a click. So the battery appeared to be completely dead.

I jump started the car and drove it around for about half an hour to charge up the battery. The battery warning light was lit the whole time I was driving. So I went home, parked the car, and figured that I'd have to jump start it and take it to the dealer this morning.

This morning I went out to the garage, opened the car door and the interior lights lit up. I tried starting the car and it started right up. It seems to be working normally now.

What's going on? Is there some "feature" that turns off the electrical system after a certain amount of time? Was my battery really dead after only 10 days? If it is a "feature", is there some way to reactivate the electrical system short of jump starting the car?

:dunno:

[magbarn]

My 1 month old (@ the time) 330i's battery also died after 5 days of inactivity. The dealer took my car and tested every main circuit and couldn't find any excessive current draw. Most of the lights in the car are controlled by the main light control module and will turn off after 15 minutes of inactivity. Some people have found their glove compartment light switch to be the culprit.

[Terry Kennedy]

Originally posted by GregD
What's going on? Is there some "feature" that turns off the electrical system after a certain amount of time? Was my battery really dead after only 10 days? If it is a "feature", is there some way to reactivate the electrical system short of jump starting the car?There's a timeout of around 15 minutes for most lighting, etc. circuits. Some things remain on past then - off the top of my head - the alarm (obviously), flashers (if on), and various memory storage in the collection of on-board computers.

If the General Module is flakey, the car may not power down as it is supposed to, even if the lights do shut off after 15 minutes. A sure sign of this on a Steptronic car is if the gear indicator LED next to the shifter doesn't turn off after arming the alarm. It should turn off immediately after arming, or after the 15-minute inactivity timeout happens. There's probably some similar hint for manual owners, but I don't know what it is...

The current draw when the car is "awake" is pretty high - it is over 5 Amps on my wagon. That can drain the battery pretty rapidly.

[Spectre]

Originally posted by magbarn
Some people have found their glove compartment light switch to be the culprit.
How the heck could the glove compartment light draw enough current to drain the battery in any reasonable amount of time? :dunno: I mean, sure, over a period of weeks, maybe....

[GregD]

Originally posted by DougDogs
Did you, by chance, leave either the left or right turnsignal on?? When the key is removed, you can turn on one side of the parking lights by leaving the turn signal in the left or right position. I don't know how long it will take to wear the battery down, but these lights will not turn off in 15 minutes.

This is a nice feature when you are parking on a narrow street at night.

The first thing I checked when I hooked up the jumper cables was to see if anything had been left on. All the lights, interior and exterior, were off.

I don't know what happened. In the meantime, I'm carrying one of those jumper batteries in the car.
:confused:

[GregD]

Does anyone know how much electricity the alarm system drains when it's activated? Could this account for completely draining the battery in 10 days?

[magbarn]

I hooked up an ampmeter with my alarm on and the current drain for my whole car was 90 milliamps. It would take about 40+ days to drain a 80Amp hour battery completely.

[Bavarian]

There's some people that wired their radar detectors in a certain way where they do not power down when you shut the car off. Perhaps you are one of such people?

[Bavarian]

Originally posted by GregD
Does anyone know how much electricity the alarm system drains when it's activated? Could this account for completely draining the battery in 10 days?

My car was sitting in the garage for 3 weeks last summer (and I have the alarm system)...no problems.

[The HACK]

Originally posted by Spectre
How the heck could the glove compartment light draw enough current to drain the battery in any reasonable amount of time? :dunno: I mean, sure, over a period of weeks, maybe....

Heck, when my key was stuck in the ignition I turned all system off to conserve battery, and the only thing that was on was the dash mileage indicator...And that drained the battery overnight.

It takes about 3 days to drain the battery with the parking lights. You can safely assume the flashlight battery probably drains what, 1/5th of that? The parking lights only draw 5w of power.

But I think the flashlights are designed to turn off when plugged in? :dunno:

[GregD]

Originally posted by magbarn
I hooked up an ampmeter with my alarm on and the current drain for my whole car was 90 milliamps. It would take about 40+ days to drain a 80Amp hour battery completely.

That makes sense to me; so the alarm shouldn't have been the problem.

[GregD]

Originally posted by Bavarian
There's some people that wired their radar detectors in a certain way where they do not power down when you shut the car off. Perhaps you are one of such people?

No radar detector in the car yet, so I don't think that's the problem. When I do install one, I'll connect it up so it turns on and off with the ignition.

[GregD]

Originally posted by The HACK
Heck, when my key was stuck in the ignition I turned all system off to conserve battery, and the only thing that was on was the dash mileage indicator...And that drained the battery overnight.

It takes about 3 days to drain the battery with the parking lights. You can safely assume the flashlight battery probably drains what, 1/5th of that? The parking lights only draw 5w of power.

But I think the flashlights are designed to turn off when plugged in? :dunno:

The flashlight wasn't on either, and as you point out it should take about 15 days for the flashlight to drain the battery although that's getting close to the variation in one battery's charge level and anothers.

I'll have to check and see if the flashlight turns itself off when it's plugged in.

[rmh]

I had exactly the same thing happen to mine about about three weeks ago after not using the car for four days. I called the BMW road service and had the car towed to the dealer. They couldn't find anything wrong.

In the service report they said:

Checked for current draw. OK withing specs. 40mA. Specs 40mA. Note: Car has only 700 miles. If car not driving often, have cust. disconnect battery. or put it on a charger.

This is the third BMW I have owned and I have never had this happen before. In fact, my 1996 328i started up just fine.

I just got back from a trip of about six days and hopefully the car will start. If not I will report back.

[vatkens]

I’m with BMW of North America, LLC. I’m so sorry to read about this problem with your new 330i. If you or your BMW center need our assistance, please give us a call at (800) 831-1117 or email us through the Owners’ Circle at www.bmwusa.com.

[GregD]

Originally posted by vatkens
I’m with BMW of North America, LLC. I’m so sorry to read about this problem with your new 330i. If you or your BMW center need our assistance, please give us a call at (800) 831-1117 or email us through the Owners’ Circle at www.bmwusa.com.

It's good to see that someone from BMW is monitoring these forums. I think I'm going to wait to see if the problem repeats before pursuing it further. I should know in about 3 weeks if it repeats since I won't be using the car for about 2 weeks starting next Monday.

[3C]

I got my battery dead after 5 months of not driving the bimmer (06/ '01 330Ci .... still with less than 5Kmiles ) , anyway got new one under the warr. :)





ps: surprisingly on the bimmer it is only 80amper hours with 3.0 engine compared to 100 ampers on 2.8L MB :dunno: -
( replacement after 2years on the bimmer compared with 5 years on the Benz )