Passenger door WILL NOT OPEN!

[Adenlamb]

Hello,
I come to you as a first time poster in need. Ill try to explain the situation as fully as I can to make it easier on those who may be able to help me.

I bought a 406 Coupe that was sitting in a farmers yard for 3 years, new battery and behold it started ran and drives absolutely fine. 99% of the electrical system seems to work perfectly including all the optional extras such as heated seats and GPS. There was evidence of mice being In the car but I carefully inspected each nest or run and found no evidence of bitten wiring or pieces of heat shrink.

The main issue I have is that the passenger door absolutely will not open in any way, along with the central locking not working( I've had 3 406s and central locking has yet to work on any of them so this isn't a major issue) .

The handle pulls were all fine, the lock on both sides of the door seemed to work and engage but the lock mechanism just wouldn't budge. I ended up finding a 2nd hand door on Facebook and took the nuclear option to drill into the lock and release it in pieces . Prior to installing the new door I inspected the wiring as closely as I could and all seemed well, I didn't disconnect the door loom from the car, rather the opposite and merely changed the door itself and lock unit with it(thinking of it now that was a very bad idea).
With the new door installed and connected all was well... For a week or two until now it has happened again. The door absolutely solid and won't respond to the handle or lock on either side.

Absolutely at my wits end with it now, this car has been brought back from the dead but this is the final hurdle. I can't afford to keep throwing doors at it but I can't seem to find enough information on how the locking system works and how I might unlock and open it.

Please, if anyone can assist me and keep this car from being broken for parts let me know, I'll provide as much info as I can.

Thanks

[hullcitytilidie]

Hi and welcome, firstly let me say there are not many posting here much and you may get a better response by posing the question on the 406 coupe oc site?
Don’t think there would be much difference between the coupe and estate models with regard to door mechs but there might be?
I had exactly the same problem with a passenger rear door recently and it would not open from the inside or outside (so not a childlock problem) I tried everything everyday for a couple of weeks.
I found that the door card can be removed from the inside (just) and it allows you to see inside and lets you to pull/push on the rods and ensure everything is moving as it should as the internals are pretty vulnerable to wet and crud accumulations. As yours, I found everything operating as should be but nothing would persuade it to open.
In the end, I emptied half a can of WD40 into the lock internals via a long straw and left it overnight. In the morning, gave it another spray and gave the lock a few thuds with a hammer via a length of a wooden stick, it opened. I could then give the lock a good flush out with WD on the actual pincer part of the lock, you could see the crud coming out as I kept operating the pincers and wiping and spraying until all was clean. No more trouble since, hope you get sorted, I fully understand your frustration. Regards Geoff.