Edit: resolved, see below...

I picked up a 2012 MCS in October 2021, and it has had issues with the driver side door closing since day 1.
All the cleaning/lube/striker adjustment in the world doesn't seem to make a difference. I tried to clean/lube/adjust probably 20 times and 8/10 times the door does not latch unless you push/hold the door shut.

I finally bit the bullet on a new OEM latch assy from the dealer, 51212752595, since the only alternative is a URO part...

After installing the new latch, I have 3 issues:
The window no longer dips/raises when the door opens/closes.
The interior lights do not change when the door is opened/closed.
The door does not lock/unlock via central locking (in car or key fob), but can be locked manually with the physical key.

The part number on this latch matched the removed latch.
I specifically remember plugging the harness in (while thinking, "wouldn't it suck to forget that.")
The mini discord recommended disconnecting the battery for 10 minutes and starting the car - no difference.

So is this a DoA latch? OR is there some sort of reset/programming procedure for the latch that doesn't show up in the TIS/ISTA that I haven't completed?

Thanks

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Edit: Turns out I'm an idiot, and the connector was not fully seated. I removed the inner door unit, grabbed the connector, and it came straight off. I reseated the connector and the interior lights started reacting and central locking started working.

For anyone doing this job in the future, the pelican parts writeup was good, except for a few things:
1. Torx sizes may vary.
2. 10mm socket required.
3. Do not remove the window motor.
4. Do not remove the mirror controls or small speaker cover.
5. After unclipping/removing the armrest, only undo the furthest aft (largest) Torx bolt.
6. When removing the big rubber gap filler at the aft end of the door, let it hang there, don't try to remove it from the door.
7. When struggling to remove the window, back the bolts out, then reach through the large speaker hole to pull the bolt back & twist to begin threading through the hole in the second bracket. Since the Aft bolt doesn't have access, pull up on the window to put pressure on the bolt while unthreading it, and it should begin threading into the second bracket.

 

Had similar connection issues with the plug. The release latch clicks into its lock position even if the plug itself is not perfectly seated (i.e. pushed fully upward against its socket).

Thanks for the tip for the forward bolt. However, applying any force from inside the glass's hole cutout (especially by using the bolt's sharp threads) risks cracking the glass. Also, if the speaker screw holes are already worn out, one should avoid unecessarily uninstalling and re-installing the speakers. The following method is both safer and faster (imho):

The end of a straight piece of wire is formed into an open loop, large enough to surround the bolt's screw but small enough to hold the bolt's head. It is then inserted through the access hole, threaded behind the bolt head and used to pull the bolt against the second bracket while the bolt is turned slightly with a screwdriver or socket on extension (both the wire tool and the screwdriver/socket on extension fit through the access hole at the same time). Once the bolt has "caught" (?) the bracket's thread, the wire tool can be removed and the bolt unscrewed completely.

PS.: Re-inserting the rear bolt is best done with a magnetic tool tip, strong enough to slightly turn the bolt into the thread without the danger of the bolt falling down.

 

Don't know if I should start another post, but I'll try just adding to this thread. I just replaced the latch mechanism on the passenger side of my 2011 Clubman. All went great and it was so improved from before. I put the door together and put everything away. When my wife got home I couldn't wait to show her. Went outside and...nothing. The outer latch...nothing. The inner handle...nothing. After loosing my s**t, I decided to leave it for a day. I finally managed to get the door open by jimmying the latch from the window slot. I proceeded to take apart the door. I took off the inner skin, and removed the bolts holding on the inner door and...the latch works. I think a higher power is screwing with me. Does anyone have any ideas as to what is going on?

Avro

 

I can't tell from your post whether the "Carrier, door trim panel" (Nr. 1 here) is removed or not.

If yes, make sure the interior bowden cable (Nr. 9 here) is fully seated within its receptacle of the latch assembly: the bowden cable must be inserted deep enough so that the marker on its outer cable (red arrow in the following picture) reaches the marking on the latch assembly (blue arrow):

 

I'll check that. Thanks

Avro