I just bought a 1997 F150 with the remote module but no key fobs. I foolishly, being able to leap tall building in a single bound and all those other things, bought a couple of fobs with four buttons to program for the 150. Nope didn't work, worked fine on DW's '02 Explorer but neyt on the 150.
Checking on a F150 site I learned a lot about the keyless systems, alarms and the like. There are stick on keypads for the door column and under the handle... I also learned about the modules, I have not tried to find anything for a E450 but if they did come prewired, you are in luck and as others have said those things you want and need for the keyless system are available. Key fobs are not all the same. In 1997 they made some major changes and none of the fobs for post 1997 Fords will work in a 1997 Ford. There are also a bunch of different modules.
I hate to answer your question by saying "Google It", but try looking for "2016 Ford E450 Keyless entry system module location", or other similar questions. Eventually you'll find the location, a description of the module connectors and the part numbers. I even found some "youtube" videos and some still photos of the modules and how they are mounted. Something else you can do is read your Ford manual for information regarding programming the key fobs. If there isn't anything in the manual, you may be out of luck. If there are instructions in the manual, you're in luck because your truck is most likely to have everything but the module.
I have a module for an Explorer that I can't use and will work in "some" F150/250 pickups and may work in your E450. If you do track down the number for a module, PM me and I let you know if my extra module will work and send it to you.
Just an aside, I hate the little red panic button on the fobs for my pickup. When I had a f150 some time ago, I took the fob apart and put a small piece of tape over the contact switch on the circuit board. I just did the same thing to my 1997's key fobs. Turns out that the circuit board for my truck is the same as the circuit board for my wife's key fob circuit board.
Her fobs are Ford and mine are Ebay, the fobs I bought the first time for the truck work her system and are also Ebay and look exactly the same and yes I can swap the CBs around to the other fobs and they work. While the housings are 4 button for the Explorer and the ones for the 150 are 3 button, the CB's all have 5 switches on the CBs. The Chinese copied them exactly and if the reliability is as good as Ford's, $5 or $6 bucks is better than as much as $90 from some Ford dealers. The same thing for the chipped keys, bought two for the DGD's 2000 Mustang for $17.00 and they work just fine.
"I travel not to go anywhere, but to go. I travel for travel's sake. The great affair is to go". R. L. Stevenson
David Bishop
2002 Winnebago Adventurer 32V
2009 GMC Canyon
Roadmaster 5000
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