Changing Battery on VW's

[ski44]

I'm putting this in Anything Auto, because this question is specifically about a Jetta, but I suppose could relate to the Passat as well...

A friend of mine has a 1.8T Jetta (2003). While he was away on a trip, his battery died. The battery was analyzed, and it could no longer hold a charge. So, he picks up a new battery and I help him install it. When we start the car up, the ABS light is lit and the Brake light is flashing and beeping continuously. I have read enough on this board to know that the problem was most likely computer related and not an actual brake fault, but I went through the checklist anyway... brake fluid looked good, ABS fuse not blown, visual inspection of brakes etc. He decided to drive it over to the dealer since we can't figure it out. Here is where it gets interesting. They tell him that any time the battery is disconnected the "computer" must be reprogrammed. They charged him for one hour of labor.

I can't believe this is true. He called VWOA and they said it's up to the dealer to decide on technical issues with the car, and they wouldn't comment on the requirement of having the computer reset with a battey change.

Can we really not change the batteries on our cars without a trip to the dealer?

[EchoOfGecko]

Yea, you'll have to reset the computer, but for the future, you can just take it to Autozone (or some other auto parts store) and they'll reset it for free. I beleive there is also a reset trick that comes from a certain ignition sequence, but I don't know what it is off hand.

You could also just get a VAG-COM, after a few loose gas caps or battery replacements, it'll pay for it's self.

[ski44]

I knew about resetting the throttle sensor, windows and radio but I was startled to see the ABS/brake warnings.

[Tom Parish]

I never had a problem with my '99 B5. Even when it was disconnected for hours. If I removed the radio sometimes I had to reprogram it. I also switched ECUs with no problems except I did have to reset the throttle body which can be done without the vagcom.

I've disconnected the battery in my '04 W8 for about an hour or two and the only thing I had to do was reprogram the navi.

[PassatObsessor]

I've taken my battery out several times, whether it was new or old. You do have to reset the computer, and it's actually very easy. Once you have the battery hooked up and everything, put the key in the ignition and turn it as far as it will go WITHOUT starting the engine. You'll hear a hum coming from the engine area. Wait about 30 seconds, or until that hum stops, then start your car. Works like a champ everytime. (This was before I got a Vag Com, so I had to figure it out)

[kodomokid]

I helped my friend who has a 2003 Jetta 1.8T replace her battery and we didn't need to reset the computer at all. All I did was just hook it up positive first then ground. Just needed to reset her windows.

My other friend has a 2002 GLI and he didn't need to reset his computer either. I think they are blowing poop.

The only thing that I can think of is if he tried to jump start his car, then he may have fried something. It is good practice to not jump our cars. It is better to take the battery out of the car and try to charge it. Hope your friend didn't jump it.

[Volkswagenmember]

hah im surprized you didnt have the battery covered under warranty, our '03 1.8T jetta had one installed like 3 months ago under warranty...