"Jim Collins" <rubidium7atcomcast.net> wrote in message
ews.com...
>I have a strange problem:
> Try to start the car with the key usually used, won't start. Put in our
> backup key, starts fine. Turn car off, put backup key 30 feet away, come
> back and can start car with first key. Turn off car, come back later
> (say 10 minutes) and first key won't start car again.
>
> My understanding is that a coil around the ignition tumbler transmits
> energy to a "chip" in the key which answers back with an ID code. This
> enables the EWS system to start the car. Once it starts, I THINK a new
> code is sent from the car to the key for storage till the next start. If
> that is true, how come it won't start the first time, but will after
> using the second key ?
>
> This all started during troubleshooting a trunk closing problem. I had
> unhooked the battery several times and the A1 module. I don't know if
> this is related or a coincidence, but there is no other issues with the
> car I know of. I have seen a programming sequence for the remote on the
> keys, but wonder if there is a similar intialization routine for the
> chip in the key.
>
> I would imagine this same system is used in all the BMW of this vintage.
>
> Thanks for your help.
> --
> Jim Collins
> Sammamish, WA

I believe the sequence you are referring to about programming the remote on
the keys is the same process for teaching the key itself to the car. Give
it a try.

Kyle.