A friend of mine had her spare key fob stolen when her house was robbed. She was worried about someone steeling her car so I disconnected the negative post on the battery. She hooked it back up and went to the dealer to get her fob and key cylinders replaced. Now they ended up ordering the wrong part so she is waiting. She told them about disconnecting the negative post and they said that was a not advised and could cause problems that they would have to charge $100 to reset. Is this true? What happens when the battery is replaced or dead?

 

I didn't get a response, would anyone know? In the past I've disconnected the battery on Honda's and held the key to the on position to clear errors.

 

People need to learn to keep their mouth shut in the society, where everything you say can be used against you. No, you cannot hurt anything by disconnecting the neg post, except that the stereo may need the code to work again, which the dealer is supposed to provide free of charge with a proof of ownership.

 

Thanks for the info. I'm figuring the important stuff gets written to non volatile ram or something that doesn't require power; otherwise you would need the dealer every time you replaced the battery. I was told that info like emissions would be lost not to mention it would cause error codes that the dealer would have to reset.

 

This is why folks shy away from dealers. Disconnect negative cable is standard procedure for just about any repair.

 

Don't even need the dealer for a radio code. Just the radio serial number. The rest of the data can be bogus.

https://radio-navicode.honda.com/

 

In some 2014+ Fiat/Chrysler based vehicles, disconnecting the battery causes all kinds of bullshit to happen. I think the steering angle sensor needs to be recalibrated, and a vehicle reconfiguration needs to be done else the car won’t know what kind of options it has or something like that.

Its been a while, but that was a memorable experience the last time I replaced a battery in a 2013 or so Dodge Dart.

(Yes I know it’s Honda tech not Dodge tech)

Modern cars are are designed to be ******* dealer magnets. Maybe not quite Honda’s yet, but in a few years it’ll be like that. A very good reason to buy older cars and not these piles of garbage that most manufacturers are putting out.

 

No lie there, Fiat/Chrysler stuff is complete **** and has been from day one.