Bought a truck recently from a private seller. Keyfob power locks were working when I looked at it and on the drive back, quit.

I've only got 1 key and I can tell the door on the driver's side has been replaced and paint matched at some point. The cylinder in the door does not match the key on the fob.

So I use a little bronze key which the guy gave me to get into the truck when it is locked, which of course sets of the the anti theft and I have to quickly switch to the fob key to start the truck. At some point I'm sure I will replace the cylinder so the kefob key opens that lock but presently I'm trying to figure out how to get the buttons on the fob ro work again.

I replaced the battery and that did not work. I tried opening the door and cranking the key eight times to program it and that did not work. The interior lock and unlock buttons on the passenger and driver side do work. Do I just pull the door panel and start poking around?

Thanks yall. Any advice would be greatly appreciated. Its a 2016 XLT Supercab with the 5.0.

 

Do any of the buttons on the keyfob work?

You can't enter programming mode with just one key fob, unless you use a scan tool. Even then, if the key is programmed the keyless (lock/unlock) and the security (start) are programmed at the same time. Meaning, if the keyfob still starts the truck, then the keyfob is recognized and should lock/unlock. So there's an issue with the keyfob transmitter, or the TPMS receiver (tire pressure and keyless use the same receiver module).

This assumes we're talking about the factory Ford remote fob.

 

You could reach out to the previous owner and ask if they've had issues in the past. They may be able to point you in the right direction.
Since it started acting up immediately after you bought it, I'd be surprised if it's a new issue. I'm not suggesting he deliberately misrepresented anything. It could be a genuinely new issue, or he could have thought it was fixed.

 

Only getting 1 fob is going to cost you about $550 to get a 2nd key cloned from a locksmith that can do key dupes.
If you go to a dealership you are looking at $1000+ for just 1 fob. If you have 2 functioning fobs you can make a 3rd & 4th key.

 

I believe Forscan, which is free besides the OBD II hardware, can now do key programming with 2015+ F-150s using the security timeout. So you can buy a Ford key online, have a dealer or locksmith cut it, then you can program it for well under those prices.

Additionally, you don't need to have the integrated keyfob if you just want a spare key that will start the truck. You can buy the side-mill basic security key, without integrated keyfob, which costs less than the keyfob.

 

If your fob is anything like my 2015 KR, there are two CR 2025 batteries in it. It WILL work with only one battery, but not for long.