its on a little card in the glove box
The keyless entry code for a 2008 Mercury Mariner is typically found on a sticker located inside the driver's side door jamb or on the trunk lid. If you can't find it there, the code may also be available in the owner's manual or by contacting a Ford or Mercury dealer. Additionally, some vehicles may have the code programmed into the vehicle's computer system, which a dealer can retrieve.
the entry code is (5) numbers on a black box on the passenger side console under the dash. all you need is a good flashlight
I found the keyless entry pad code under the center console. You will need to pry the bezel trim off first. It has friction grips and will pop out. You can then remove the center console enough to find the black electronic control box. The original code is on the black box on the driver side of the console frame.
You can find the keypad entry code for a 2005 Mercury Mariner in the owner's manual. You can also find it by contacting the dealership.
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I have a 1998 and the code is in the back where your jack and accessories are.
Each vehicle with keyless entry has its own factory code
the keyless entry code is inside the cover in the back where the rear windshield washer container is
there is a "wallet card" which has the code on it, if you do not have this card you will need to bring the car into a Mercury dealer and they will "plug it in" and retrieve the factory preset code.
its in the trunk on a sticker or under the hood or inside the door
You will find a sticker in the trunck with the factory code printed on it.