Radio code not working!

[BrandC]

I disconnected the battery on my '91 318is and now the stock radio won't accept my radio code. It worked one time and now it won't work anymore.

A friend of mine who works at the dealer said if you leave your key in the ignition at the "ON" position for an hour, it resets the radio. I'm not sure if this really works, haven't tried it.

Any suggestions?

[SchnellerVert]

Why would you doubt him? That is the proper method.

[BrandC]

Why would you doubt him? That is the proper method.

It's not that I doubt him, I just haven't tried it and know anything about this method.

So if I leave the key "ON" for an hour, I should be able to play the radio again?

[strad]

Just do it, only do it for about 1.5 hours just to be safe. Longer isn't going to hurt anything, and may be necessary on some cars. After that, enter the code and you're golden.

[jlevie]

If one is going to leave the ignition on for an hour to clear the theft protection lockout in the radio, I'd highly recommend doing that with a 10A or better battery charger connected. Especially if the battery has a bit of age on it and has "less than new capacity".

[BrandC]

I will try this method and keep a charger handy. Thanks for the replies all.