Ford Focus 1998 Central locking problem?

Remote doesn't work at all (I have changed battery). Manual key works fine. I don't get any lights flashing when I manually lock doors? (I don't know if this is relevant. Maybe lights only flash if using remote). Tried turning key 4 times in 6 seconds; but the car doesn't beep. I was told to reset central locking, by unplugging three plugs in unit behind panel beside right foot in drivers well. There were only two plugs, and it didn't work. Then heard to disconnect two plugs next to this unit (on the remote sensor). There was only one plugged in (??? the other was taped up to stop it hanging loose; but there wasn't anywhere I could find to plug it in...is this the third plug that is supposed to be plugged into the main unit? I didn't try to plug it in as it didn't look like it would fit). I haven't tried changing the fuse yet as it sounds difficult to get to (behind main fuse box behind glove box). I also didn't disconnect the battery (either on its own, or while disconnecting the remote sensor). There I think that's everything...can anyone offer any advice?