I've been searching pretty extensively in the forum for door lock issues and know there is a ton of info about it, but figured I would join and post my specific scenario. My wife drives a 2003 Disco and recently told me she cannot unlock the doors using the remote. God knows how long she was having issues (i.e ine door at a time failing).... But at this time:

-All 5 locks cannot be unlocked using the remote.
-interior dash switch locks but not unlocks
-can hear the actuator try to unlock the locks, but no joy
-flashers flash when the button is pressed
- all locks can be locked using the remote
-issue started intermittently (for all locks) in a cold night was the first symptom

Assuming all locks stopped working simultaneously, rule out actuators? Could it be the IDM? BCU? Also have a wiper issue, only works full on, gets stuck when using the quick wipe function. No starter issues or any other BCU related problems I have read about. I am an electrical engineer and comfortable troubleshooting, where should I start?