I've also been fighting the lock cylinder on the driver's side door. It turns out there's nothing wrong with the lock cylinder. It's the key that's worn out. So, I looked up transponder keys and I see Amazon has blank sets of two for around $15. Has anyone purchases these keys online and had them cut locally?
Ok, so I’ve been down this road…
First, if you haven’t already done so, hose the lock out good with electrical contact cleaner (it’s plastic safe) and work the key in and around while you’re at it. Sometimes gunk builds up in them and the key doesn’t work right. It’s worth a shot, I’ve had some success with that.
Buying chip keys online is a mixed bag. Sometimes the chips don’t work or aren’t compatible and once in awhile you hear about ones that are sold as chip keys and don’t actually have a chip in them. So make sure it’s a reputable source.
Home Depot and some other places can cut and ”program” chip keys for less than the dealer or a locksmith. But what they do is “clone” your key. So they duplicate the cuts on your key and program the chip to match your key. Thus if you only have one chip key and you get one made like this, you can’t use those two keys to program a third on your own because the computer sees both keys as being the same key. The other thing is, if your key is getting worn down, they don’t cut it to original code, they just make a match to your worn key. So if you don’t have a “good” key, you still need a locksmith or dealer to cut a “good” key and possibly program it.
Now, the solution I found when I was in your boat back a few years, I found a locksmith on eBay, Wolf Security was the name, he had me send a good close picture of my key and sent an unprogrammed key cut to code for about $20 or so. Armed with Forscan on my laptop and a usb to obd2 cable I programmed in the new key. A year or two later I finally got myself a basic key machine since I like to tinker with locksmithing and came up with a bit of a plan. Now if it’s a chip key, if I have a good original key (or have one code cut), I retain that for a spare AND cut a non-chip key that goes in the spare box with a tag. Now I will always have a near perfect key to cut from for that particular vehicle. Then I have two keys for regular use, since I always carry a primary and spare with me. If it’s a chip key, I maintain two spares at home too (since it’s reasonably cheap for me to do so), thus I’m always going to have a good mechanical cut and a pair of chip keys to program with. I only buy Strattec chip key blanks for the Fords and usually try to use them for other brands. Strattec is the OEM key for Ford, so programming is not a problem.