Another Key Question!
 

Hi! I've gone through all the threads but none of them apply to my situation. The spare key (full remote) would unlock the doors/tailgate but did not drop the windows if you hold onto the unlock button. It does not lock the doors nor close any open windows.

It won't start the engine unless I place the working key into the barrel and turn it to position 1 then remove it and put the spare key in. I can then stop the engine and restart with the spare key BUT if I wait 15 secs or so then the spare key won't restart the engine.

I tried to reprogram the key today using both methods and now the spare key won't open/close anything and the starting issues are unchanged.

Any help would be appreciated. I'm thinking the battery must be near death and will probably need to try and change the battery as outlined in previous threads.

Cheers

maybe you can get a car key programmer reprogramming your key.
bmw ak 90,bmw ak 300,bmw ak 500 which on get depend on what model and year.

Good day!

There are essentially two parts to the workings of the key... The remote unit and the ignition unit...

Anyone can program the remote unit and is controlled by a battery... If the battery is weak, it may not register as you have found out with it not unlocking the doors anymore... Additionally, the unlock specifics can be designed by the user to set the seats and mirrors to preset 1 or 2 or 3 when the remote unlocks the vehicle... I believe (not positive) that you can have it set to NOT roll down the window too... However, that may be a result of a weak battery too...

The ignition unit in the key is controlled by electrical field around the ignition cylinder... Once energized, the EWS module recognizes the key if it is programmed by the dealer... If the key isn't recognized, it won't start the car... HOWEVER, if you start the car with a working key, then swap it out for ohhhhhhhh, say a valet key, it will operate the vehicle as long as it is running, and only a few seconds after if the vehicle should die (manual trans clutch release too fast) before parked... Once parked, the valet key becomes worthless to a thief...

Options: Get the key programmed by the dealer to operate the EWS and start the vehicle... Replace the battery...

OR Get a new spare key from the dealer for about $145 (US) which includes programming... Bring your other working keys or they won't work after the new one is programmed...

Good luck!!

Cheers!!