Replacing battery without radio code

I want to replace the battery in my 2003 Jetta wagon because I need it for a genset that I am building plus 4-1/2 years on a battery is probably pushing it. Is it sufficient to follow the procedure in the service manual or are there gotchas that I need to know about? Also I can't find my radio code which is mentioned in the SM. A friend who has a Beemer said he bought a battery saver from BMW which he plugged into the cigarette lighter and it kept all the system info while he changed the battery. Will this work in a TDI and if so where do I buy one?

George

On the 2003's I believe that the radio is "mated" to the other modules and as long as you don't swap radios, you won't need the code...

Yuri.

ymz said:

On the 2003's I believe that the radio is "mated" to the other modules and as long as you don't swap radios, you won't need the code...

Yuri.

Click to expand...

Yes, when I replaced my battery, no code needed. 2000 TDI

I replaced the battery on my Jetta and my daughter's Jetta and didn't need the radio code. I just tried to minimize the time that the battery was disconnected.

If you are really worried about it you can plug a nine volt battery into the cigar lighter socket. Either DIY or buy one at the car parts store. You can then take as long as you need to replace the battery, clean the drains, etc. Odds are you don't need it, but you can never tell.

Be aware that the 9 volt battery is capable of the milliamp current needed for radio code and memory, but not for the amount needed for interior lights or other items. Trying to run the dome lamps on the 9 volt will drop the voltage to a level that the radio will lose the memory.
Also note that this only works on vehicles with the radio memory power and lighter power from the same fuse. If the lighter power isn't shared with the radio memory power, then supplying lighter power from another source (saver) can't supply power to the radio memory.

Install the saver.
Pull the fuse for the radio to separate this circuit from everything else.
Then disconnect the main battery.
Re-connect the new main battery, install the fuse and then remove the saver.
The VW solar panels are perfect for this instead of a saver, but you still need to pull the radio fuse because the panel's output amperage is too low.

2000 TDI - never had my radio lockout while changing a battery.

For the last 4 years in December I have changed my battery from the standard one to a tractor battery during winter and back to the standard one in spring. Only once did the radio go into secure mode. This was when I left the battery out overnight. Typically it is out (without any other source of power) for 30 minutes +-

Ken