I purchased on 05 Mariner yesterday and it didn't come with the owner's manual. I've been looking for anything that has the factory 5 digit code for the keyless entry everywhere!

Where do I need to look so that I can fix this, in case I lock my keys in my car?

 

I have seen it on a sticker in the trunk, some have sticker in the glove box.The code for most SUV's is usually located on the Vehicle Security Module (module that controls your electronic locking). Hope this helps.