Pretty sure the MCS needs new battery.

FC · 06-26-2012, 08:49 AM

A quick Northamericanmotoring search yields dealer prices of ~$300 vs. ~$100 from car parts stores. But it also mentions something about the dealer having to reset the car's computer so that it knows it has a new battery as it can affect power mangement or something like that. Others say they did a simple swap with no issues.

Anyone know anything about this?

Battery can barely hold a charge after a long drive so we are not using it right now.

Mini dealership is annoyingly far, even if I could get past the steep price (which I can't right now). I'd have to see hard evidence of damage from aftermarket batteries before I drive that far and fork that kind of dough for a battery.

ff · 06-26-2012, 09:00 AM

If I owned a car that was designed such that the battery had to be replaced by the dealership to the tune of $300, or it would fail to operate correctly, I'd drive the car through the front window of their headquarters, throw the keys on the president's desk, and walk away forever. That being said, I have a hard time believing that even BMW would stoop to that level. Take it to an auto parts store and see what they say.

JST · 06-26-2012, 09:01 AM

Quote:

Originally Posted by FC

A quick Northamericanmotoring search yields dealer prices of ~$300 vs. ~$100 from car parts stores. But it also mentions something about the dealer having to reset the car's computer so that it knows it has a new battery as it can affect power mangement or something like that. Others say they did a simple swap with no issues.

Anyone know anything about this?

Battery can barely hold a charge after a long drive so we are not using it right now.

Mini dealership is annoyingly far, even if I could get past the steep price (which I can't right now). I'd have to see hard evidence of damage from aftermarket batteries before I drive that far and fork that kind of dough for a battery.

That same issue ("registering" the car's battery) has come up on the E60 boards. I have no idea whether there's anything to it--as with NAM, some people swear up and down that there's no issue, and others claim to have all manner of battery problems if they don't do it.

I am not an EE, but the whole thing doesn't make sense to me. Batteries wear and die at different rates depending on conditions. Why would you design a system that charged a battery differently based solely on time? Is there a concept here that I'm missing?

bren · 06-26-2012, 09:01 AM

"Battery can barely hold a charge after a long drive" sounds more like an alternator than a battery.

FC · 06-26-2012, 10:09 AM

Quote:

Originally Posted by bren

"Battery can barely hold a charge after a long drive" sounds more like an alternator than a battery.

Thought the same thing, but even with the JGC jumping it, it had trouble starting, so that points more to the battery.

Regardless, the battery is pushing 5 years, so if not now, it will be due very soon. Might as well start there and see what happens.

FC · 06-26-2012, 10:13 AM

Quote:

Originally Posted by JST

I am not an EE, but the whole thing doesn't make sense to me. Batteries wear and die at different rates depending on conditions. Why would you design a system that charged a battery differently based solely on time? Is there a concept here that I'm missing?

I don't buy it either. Just asking if anyone knows anything that could explain somethind so goofy.

I suppose a system could be designed where it keeps track of temperatures at starts, charge rates, alternator demand, etc, but that would be way to complex and expensive versus the decades old system for such a small benefit (if any). It's just a bettery and it will eventually die anyway.

John V · 06-26-2012, 10:37 AM

It's easy enough to check the alternator, but I'd just replace the battery.

Be sure you disconnect the battery before replacing the battery. You know, so the ECU resets.

kognito · 06-26-2012, 10:48 AM

Quote:

Originally Posted by John V

It's easy enough to check the alternator, but I'd just replace the battery.

Be sure you disconnect the battery before replacing the battery. You know, so the ECU resets.

yes, makes it much easier to install the new battery if you disconnect the old battery first. (Sorry, couldn't resist a comment of the humor of your typing)

FC,

Simple Ohms law. If you are having problems starting when jumping, something else is wrong. I needed batteries (4 of them!) on the Volvo 9 months before I replaced them. I used to jump start that 14.9 liter diesel with my Malibu. I would just hook up the car, and start the diesel motor, no charge time, no revving, just hook up and start.

Something might be wrong with your starter cable, ground cable, or other connections if you are having trouble starting it with another vehicle.

O'Reilly, NAPA, Autozone or who ever will test your battery for you for free.

John V · 06-26-2012, 10:53 AM

I was inspired by the shop manual for my Triumph which in the "battery removal" section has a preface to "always disconnect the battery before making any electrical repairs." Duh.

kognito · 06-26-2012, 10:58 AM

Quote:

Originally Posted by John V

I was inspired by the shop manual for my Triumph which in the "battery removal" section has a preface to "always disconnect the battery before making any electrical repairs." Duh.

holy shit, I know exactly what you are talking about. Triumph had that in my GT6+ manual

06-26-2012, 08:49 AM	#1
FC Solving problems Join Date: Oct 2003 Carmudgeonly Ride: M5 / 718 GTS / Cooper S / GTI / LR4 Location: Metro Boston Posts: 25,264	Pretty sure the MCS needs new battery. A quick Northamericanmotoring search yields dealer prices of ~$300 vs. ~$100 from car parts stores. But it also mentions something about the dealer having to reset the car's computer so that it knows it has a new battery as it can affect power mangement or something like that. Others say they did a simple swap with no issues. Anyone know anything about this? Battery can barely hold a charge after a long drive so we are not using it right now. Mini dealership is annoyingly far, even if I could get past the steep price (which I can't right now). I'd have to see hard evidence of damage from aftermarket batteries before I drive that far and fork that kind of dough for a battery.

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06-26-2012, 09:00 AM	#2
ff . Join Date: Mar 2004 Posts: 13,514	If I owned a car that was designed such that the battery had to be replaced by the dealership to the tune of $300, or it would fail to operate correctly, I'd drive the car through the front window of their headquarters, throw the keys on the president's desk, and walk away forever. That being said, I have a hard time believing that even BMW would stoop to that level. Take it to an auto parts store and see what they say.

06-26-2012, 09:01 AM	#4
bren lawn boy Join Date: Oct 2003 Carmudgeonly Ride: e46m3, f25x3,C5 Z06, C4 Vette, 06 CTD Ram, and a trailer Location: Maryland Posts: 14,029	"Battery can barely hold a charge after a long drive" sounds more like an alternator than a battery.

06-26-2012, 10:37 AM	#7
John V No more BMWs Join Date: Apr 2005 Carmudgeonly Ride: Ram, MS3, CX-5, RX-8 Location: Glenwood, MD Posts: 14,753	It's easy enough to check the alternator, but I'd just replace the battery. Be sure you disconnect the battery before replacing the battery. You know, so the ECU resets.

06-26-2012, 10:53 AM	#9
John V No more BMWs Join Date: Apr 2005 Carmudgeonly Ride: Ram, MS3, CX-5, RX-8 Location: Glenwood, MD Posts: 14,753	I was inspired by the shop manual for my Triumph which in the "battery removal" section has a preface to "always disconnect the battery before making any electrical repairs." Duh.