Wonky central locking

[FarmerPug]

Another issue on the Citroen, but hopefully the same techniques apply to it as the 406.

Ive fixed the door looms, and changed the passenger front door, it now closes and the MFD doesnt show it as being opened anymore, which is good.

But the key still doesnt lock the car, with the key at the moment i can do the following; unlock the car, unlock the boot (its a fancy feature the xsara gets, but it only unlocks it, no lifting itself up), and when i press the button on the key to lock it locks, but instanlty unlocks again.

If i put the key into the door the car locks, and unlocks, if i lock it with the key in the door, i can remotely unlock it ok.

And if im sitting inside the car i can lock all the doors from the drivers seat.

The only thing i suspect as a problem is one of the back door mechanisms, the rear passenger one is a bit noisy when locking.

Any other ideas of what could be the problem.

[GingerMagic]

Could the boot lock also prevent the doors from locking?

[FarmerPug]

It would if the boot was opened, but it closes ok, the button on the key simply unlatches it so you can lift up the boot.

[lozz]

Spray all the mech's. Wd40 to start with then some 3 in 1 sort of oil,

[FarmerPug]

its still not working, i put a different rear mechanism into the rear passenger door, same problem.

So i disconnected the rear door from its loom, they plugs from the B pillar to door unplug easily, and with it unplugged the car doesnt see any problem, but still the other 3 doors wont lock remotely, i tried disconnecting each door individually, and then tried unplugging all doors bar one to see if one would lock but still no.

So it only locks with the central locking by physically putting the key in the door and turning it, or sitting inside the car and pressing the lock button on the door.
But pressing the remote control lock button makes it lock and unlock at the same time (ill try and post a video), this one has me confused.

[GingerMagic]

Could it possibly be the key..??

[FarmerPug]

It could i suppose, but the key is sending the signal to the car ok, it does everything but lock the doors fully, i wonder has it got messed up in that when it tries to send a lock signal its simultaneously sending an unlock signal, i have a new blank key with transponder in the post (its a bit risky having only one key)
Its an unusual fault though.

[GingerMagic]

Check the key on PP2000, it will show if the unlocking or locking request has been pressed on the key.

Can't remember where in PP it is though, it may be under replacement parts?

[FarmerPug]

Will try that Ginger, Lexia is a tad different but most of the options are there.

Here is a quick video showing the issue:
USpxVOGeIms

[FarmerPug]

I went into Lexia there is no option to test the key, but there is an option to lock and unlock the doors as if pressing the buttons on the key, but the central locking still tries to lock then unlocks.

I can hear a click noise coming from the BSI, is there relays inside the BSI that could be damaged or corroded?