I see there are several threads on the issue of rear door locks not working but I couldn't see one covering my issue. The right side rear door will lock and unlock when done manually from the door catch inside the door itself but will not lock or unlock from the remote. When the remote is used the handle on the inside of the door moves a little but not as far as the handles on the other doors, so it is activating the mechanism but it seems to lack the power to complete the lock/unlock.

 

Can you lock and unlock the problem door electrically using the buttons on the dash or door? (unsure what MY you have). My 2012 sometimes has a software issue with the left rear door, but the mechanism is good since I can use the in-car buttons.
You may likewise have a software module problem, or the actuator itself is faulty. Let us know.

 

Well, when I try and unlock all doors electronically from the driver door the rear right door lock handle "twitches" but doesn't move enough to actually unlock. Same when I try to lock all doors from the driver's door. It's a 2011 car.

 

Usually when the inside levers don't move all the way that indicates a bad actuator. So you may have to change it. With the amount of use the lock actuators get I would only install new units. Mainly because of the amount of work required to change lock actuators. They are buried in the door latch mechanisms.
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Thank you very much for the input. I will prepare for the worst!

 

Well maybe easier than I thought? It's definitely a DIY job but removing the window glass looks like a pain.
Look at this very detailed thread from the UK forum. Seems to be just what you need?
Front Door Lock Actuator
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In looking for an actuator I note that they can be bought on eBay for about £55, Presumably these are Chinese knock-offs, but I dread to think how much the authentic Jaguar ones are. Anyone had any experience of them?

 

Not really but if you post a link we can take a look?
I know what you mean but I have found (surprisingly!) that most of the Chinese knock off stuff works pretty well?
I purchased 4 TPMS sensors for $30 and they work perfect and compared to how much the Jaguar dealer parts department charges it was worth a shot!

Just for fun how much are the factory actuators? I know the door latches are in the $300+ range! But to be fair they are complicated latches with multiple sensors inside them.
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Here is the link to one of the eBay ones.

https://www.ebay.co.uk/itm/115876906...mis&media=COPY

 

For that price if it matches yours I would just get it. I don't think you have yours out yet?
I would make sure you get the right variant as he does not have the soft close one so it won't work on 2014 and up XJ's. Yes all XJ's use the same mechanical latch so they do fit all 2010-2019 XJ's technically. Not sure if not haveing the soft close plug attached would give any errors so maybe the only downside is loosing soft close on that back door.

But with the 2011 model you have I would check number of pins in the plug like he mentions in the ad. I bet it's the right one.
He is in the UK and gives a 2 year warranty? At least you have a contact.
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