You can program the ECU to recognise 2 keys, you need both keys to complete programming.
1. Ensure ignition is turned OFF
2. Press central locking door button for more than 5 seconds.
Do the following within 15 Seconds. Basically this bit simply allows the ECU to 'copy' the key signatures and remember them:
3. Point both keys at the roof console.
4. Press a key button twice (once on some models)
5. Press the other keys' button twice (once on some models)
(Doors will lock / unlock)
6. Test both keys.
Yuri
November 2008