When did cars get so smart??

[billb]

My neighbor has a Boxster S, a '99 328, and a 2007 E61 530xiT. Yesterday morning, I looked outside to see the trunk open, the hood up, and the car sitting in the middle of the culdesac, blocking my driveway. They had backed it out of the garage, and got to the bottom of the driveway, when it just completely quit. Wouldn't start, low battery voltage, etc. I went outside in PJs with coffee, and offered to help. Checked the battery, 9.7V. Hooked up my charger to it, and it was recovering to 12.3 volts within a few minutes. But as soon as I tried to start it, huge drop back down to ~9V. Diagnosed as dead battery.

Here's the kicker; you can't just install a new battery...it has to be synchronized to the car. They will have to flat-tow the car to the dealer, install the battery, then tell the car not to overcharge the new battery...

Love the fact I can drop a new Interstate under the backseat and keep on trucking. :)

[whiskychaser]

Couldnt they just swap the batteries as you would if you didnt have the radio code? Wonder how they synchronise a battery.

[Tiger]

It is a dumb thing but I believe it has something to do with the high tech voltage regulator used in modern cars nowdays... Cadillac has it too. It is stupid.... the voltage regulator will charge the battery at 15.5V... which literally cooked the battery. The funny thing is that my voltmeter shows charging of 15.5V but the car internal OBD voltage meter will only show 14.2V.

It is a blessing to have 'dumb' voltage regulator like what we have... but eventually as we upgrade our car... we will hit those high tech voltage regulator. I think BMW just need to 'reset' the computer to tell it that new battery is installed.

My friend with the Cadillac... two of them... has tons of electrical problems in their cars.... not just the battery.

[Jr ///M5]

Yup, you own a new BMW and the battery goes dead, it's a trip to the dealer. The real beauty in the E34, battery wise, is the fact that most of mine lasted about 7 years before needing to be replaced. New cars today get about 3 years before they poop out, and the electrical dependency is the cause.

[billb]

The latest is that they had it towed to Leith in Raleigh, and Leith proclaimed it needed about $3500 in repairs. Funny how everything was fine and dandy while it was in warranty...
Leaking transmission $1500
Alignment $300
Rotate and balance $150
Battery $300
Install battery $100 (you don't think they'd do that for free, do you?)
Synch battery $200 (and you wouldn't think they'd synch it free either?)

And another grand of miscellaneous stuff...

[Tiger]

Insanity! $300 battery? $600 to install a new battery?!

[Tiger]

Update on that battery sync thing... it is all BS!

Battery Replacement - 5 Series Forums (http://forums.5series.net/topic/68522-battery-replacement/)

All expained in owner's manual. You can use any battery you want.

[whiskychaser]

Insanity! $300 battery? $600 to install a new battery?!
Dont really understand why you couldnt connect the new battery to the car's leads with jump leads then swap over. No resetting at all then. My battery cost equivalent to USD100. USD 800 is a heavy penalty for not reading the handbook.

[Bill R.]

Hi Bill,

I've had to do a couple of those, in fact i did a xiT last weekend. One of my customers had just bought a used one, came to town to visit his family and the battery died.
The battery has to be registered to the comp to maximize the life of the battery. The charge rate is regulated according the the CCA and the amp hour rating of the battery.
As it ages the charging rate from the alternator is adjusted accordingly.
Bmw here wanted just under 450, 240 something for the battery and the rest labor. We put a 8 year autozone duralast in it that had the same cca as the old one. Its the same autozone battery i put in the e34's.

The autoenginuity enhanced scan tool registered the battery but i don't think it was even needed. The AZO battery is warranteed for the same time period regardless of what the charging rate from the alternator is. This kids factory battery only made it 4 years so the registering didn't seem to do much good anyway, since thats about the normal life for a battery here.

[Dave M]

Sounds like a great deal. Pay 4-6 times the price of a battery with no perceivable advantage.

Dave