My Fiesta is a 2000 Mk 5. Just lately I started having problems with the remote key. Sometimes it works fine even from about 30 feet away, and other times it won't work even when I'm beside the car.

I came back to my car today and it was raining so I was pressing away at the button and it wouldn't unlock the doors. I finally opened the door by using the key in the driver's door and when I opened the door the alarm went off.

I put the key in the ignition and started the car thinking this would stop the alarm but it didn't. I switched the ignition off again removed the key and pressed the button about 20 times before it finally worked.

Next time I tried it the remote worked fine as usual. Does this sound like a faulty key remote or a fault in the car itself? I'm out of work so I don't want to spend money on a new key and getting it coded if it doesn't cure the problem. Also I have put in a new battery and checked it first using a volt meter to make sure it wasn't a dud.