janoeterm

For the second time within two weeks, I got an error on the display that I had to reset time and date. The first time was after a cold start, the second time was after starting a warm engine. Next to time and date being lost, I also noted that the day trip counter had been reset to zero. Both times, the car started normal, that is, it usually cranks a bit slow and comes to life with a forceful shudder. The car has been checked at a BMW dealer recently, but no mention was made of a weak battery. Is it the battery and if so, can I replace it myself?

Thanks,
Jan
Plymouth, MI
2007 530xi m6, 95,000 miles

Holtz

You could change you battery yourself, but it needs to be coded to the car after the change.

JayArras

Battery replacement is a topic that has been discussed widely on this forum. Do yourself a favor and type "battery replacement" in the Search box. After reading all of the posts, if you still have questions, feel free to post them.

TwoPedal

It sounds like a weak battery to me, as well. My car started to reset the same items and my dealership said the battery was fine until it died in their driveway and would not start.

The battery is easy to replace, but as jayarras said, it is a widely discussed topic. BMW claims a new battery must be "programmed" to the car for smart charging purposes. Some people adhere to it and some do not.

yeewiz

I had a new Autozone 95R-DLG installed last July. Since it had the same specs as the BMW battery, my indie mechanic said nothing to program. At that time I bought a Battery Tender and use it whenever the car may be idle for a couple of days or more.

So here's what's weird: If I have the BT on and don't drive the car for a couple of days, the time disappears when I go to start the car (with BT disconnected). If I don't have the BT on and don't drive for a couple of days, the time disappears too. Date is fine though. If I drive the car everyday, the time is fine. No other settings appear to be lost.

Any ideas?

Lotus99

Isn't that exactly what the programming is theoretically supposed to prevent? The car thinks you're still using a battery that's x years old and can only hold a certain amount of charge, hence it's not charging it to its full capacity, and you're having issues. That's the theory behind why it needs to be coded, so the car knows it's a brand new battery, and how much to charge it before it's "full". Sort of like the memory effect you hear with the old rechargeable Ni Cad batteries.

I have read of a few others in the E60 forum though saying they've run a few years on a replacement battery without coding it, but don't know their circumstances, and whether they drive it every day, etc.

Quite a few justified it by saying that even if the battery dies after a few years, with the money they saved on the non OEM battery and not paying for coding, who cares if they have to replace it every 3 years, instead of every 5.

Good luck and let us know what you find out.