Relays are those little black square boxes in the fuse box. You can check those by switching with known good one elsewhere in fuse box, but remember to put the good one back in it's place, or buy one used ONLY for checking relays.
I suspect your problem is the device in the door that pops the lock open and closed. They aren't that expensive usually if you know how to remove the inside door cover and replace it yourself.
Hi,
I've got a 2008 Ford Focus that came with a key fob and then a backup standard key (no fob).
I've been using the fob for around 2 years with no issues. Then about 6 weeks ago it wouldn't unlock the car. So I presumed it was the battery and bought a new one. No luck!
On 9 days out of 10, the key doesn't work to unlock the car. So I have to use the key in the door and the start it quickly before the alarm goes off.
Then, when I turn the ignition off it doesn't lock either using the key fob. However, if you put the key back in and click the key round (don't actually start it), turn it back off and take the key out, the key fob will work to lock it.
Any suggestions on possible fixes? Would ideally fix myself if possible.
Thanks in advance!

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