I've activated the dipping mirror and didn't need to use a security code. If you got to the Passenger Door Electrics, and look at the coding there, there's the option to activate and then select 'memory mirror' or something to that effect. If memory serves me correct, there's also a third option relating to electric memory seats which i don't have so left well alone. I think there may also be an option in the coding on Central Electrics but i can't remember? Then select 'L' on your mirror adjustment switch. Mine doesn't always go back to the exact same position (it's better now i selected mirror memory), but it works fine otherwise - i tend to activate when i need it and leave off at other times.