The unlock passcode for 05 Mercury Grand Marquis driver side
There is not a generic code for this system, if you didn't set in your own code when you purchased the car then your stuck with the factory setting, in your case I would recommend getting a lock out service or a locksmith to go out an open it for you then read your owners manual on how to set your code for the keyless entry.
If you don't have the factory code you will need to get it from a Ford/Lincoln dealer then you can set you own code. BEWARE some dealers may do it for free up to $100. Of course how much is a locksmith everytime?? Good luck.
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