Keyless entry code for 2003 Explorer
Not sure on the 2003, but on the 99 its located in the back behind the panel that hides the jack on the driveds side.
You have to get a flashlight and look really carefully back in there to find it. Once I saw the module with the code on it I really had to strain to read the code. On the 99 the code is 5 digits.
Hope this helps.
Carlen