MrTantrum

I posted this on bimmerforums also, but not sure of proper etiquette nor if same owners frequent both sites.

Okay, I've read extensive threads on potential electrical/battery drain issues with the 5 series (I have a newly purchased 2008 535i with 32K miles), but I don't think that they directly address the issue I'm experiencing. I've had the car for 4 days now, and last night had to jump start it. Here is my scenario:

1. I purchased the car from a non-BWM dealer. However, it was a one owner lease vehicle. I determined the original dealer and called them to get the service history. All recalls had been applied and the service history was impecable.

2. The car had been with the dealer for at least a week and probably had not been driven for at least 2 weeks.

3. The first night I had the car, I sat in it with the engine off for about 30 minutes figuring out the gadgets. I received an electrical warning, but I was able to start the car, drove it around the neighborhood and everything seemed fine.

4. The next evening repeated the above but for only about 15 minutes.

5. Last night repeated the above but for only about 10 minutes but car would not start (had to jump it).

6. Each day have driven the car about 20-30 miles, partly highway but mostly city. Every morning after sitting all night the car starts fine so it is not draining power over night.

So, here are my questions:
- Do you think I need a new battery or do I just need to get a nice long highway drive under my belt to get the battery recharged?
- What is realistic as far as time that I should be able to have the car in accessory mode without the car running and listen to the radio, etc.?
- If I do need a new battery, have any of you had luck putting your own 3rd party one in (I realize there are threads that address this, but wanted to ask in context)? By the way, where exactly is the battery in the 535i?
- Any other advise/input would be appreciated.

BMW535

I also have 2008 535i. I purchased it in 2007 and had to replace the battery after 3 1/2 years. Lucky for me the car was under warranty and the dealer changed it at no charge. If you car is still under original factory warranty, take it to the dealer. What it sounds, if the car still has the original factory battery, it may be time to chnage it. As far as the battery location, it in the trank, right side, remove the two plastic screws and pull the cover.

MrTantrum

Unfortunately, no factory warranty left so I am on my own. Dissappointing for a new purchase, but I don't want my wife to get stranded and lose confidense in the vehicle.

louisrai

I had the same thing with my 08 535i. When I bought the car in 2011, the battery failed many times, I had to replace it on my own, that costed about $150. However, I do have a question here: is the Battery Vent Tube necessary? I didn't put it up.

MrTantrum

Did you have it "programmed" by a dealer/autoshop after you installed it?

pukka

The OEM battery lasts about 3-4 years.

If you replace the battery with another OEM or an aftermarket one with identical specs - you are supposed to have the battery registered in the car computer

If you replace with a battery with different specs then you need to prgram the changes in the car computer.

The coding is supposed to ensure the car properly charges the battery and prevents premature failure or overcharging. Some people on this forum didn't get the reprogramming and had no problems - so it's all up to you to decide what to do.

MrTantrum

Can anyone here who has replaced their battery with equivalent 3rd party and NOT gotten it registered personally attest to any negative reprocussions?

louisrai

No, I didn't do anything other than putting it in...it is a Interstate battery. It worked okay, until last weekend, it failed once.

jaycal3

In Texas is there no 30 day warranty on all used vehicles purchased? That would help... and at the least, you should at least attempt to contact the dealer from which you purchased the car.

I have sat in my 545 which is an '04 for up to an hour with no engine running listening to the radio while my kids are at practice and the car starts right up.

MrTantrum

Used vehicles are always labeled 'as is' and 'no warranty', but I don't know if they have an obligation or not. Even so, I will send dealer rep an email to see what they say.