Hi Guys,
I copied and pasted this from another post that was never answered, but I am having the same problem.

All passenger doors quit working in most circumstances.
1. Key Fob single press - Lock and Unlock works on drivers door and rear door only.
2. Key Fob double press - Locks all doors but will only unlock driver and rear door.
3. Key Lock single turn - same as key fob#1 above
4. Key Lock double turn - same as key fob#2 above
5. Internal lock switch - only locks and unlocks drivers side door

Alarm enables and disables without issue.

Anyone have any ideas?

 

Sounds like IDM module which is part of fuse panel. 4 Relays in it apply power or reverse power to lock motors. See attached schematic. Or you could have a broken wire between the relays and one of the headers where it goes to multiple directions. The RAVE electrical guide will show you the headers based on that tiny number beside each wire. Or you could be cursed with multiple bad lock motors. They don't have a "ground" as the motors are fed polarity that reverses to make motor run bassackwards and unlock. Will need to fix before you get it stuck in superlock mode and can't unlock.

 

Thanks Savannah. I can't find a fuse box in the passenger side foot area. Is it talking about the one under the hood? I forgot to mention, it's for a 2001 Discovery.

 

Its under the steering wheel (passenger side in the UK with right hand drive)

 

I found the fuse box! Lol. I checked the number 1 and 20 fuses and they are fine.
When I lock the doors with the remote and central lock switch, the passenger door locks but will not unlock. When I try to unlock the mechanism moves a little, but not enough to unlock. This happens also at the (2)rear doors. The back door works fine. Does this sound like 3 bad lock motors or something in the wiring.

Thanks.