Central Locking issues

[liddell]

96 model 1FZ-FE

Hoping someone can help me with a Central looking system on my 80.

I've got an alarm that when armed and disarm the Central Locking system locks or unlocks the 80 no brainer. lol

However lately it hasn't been locking on the arming side. I would have to lock with the key in the door to lock all doors.
(so I figured I have the wire is broken from the alarm to the lock wire)
Hadn't got there to look at it yet. However now I can't lock it with the key either now. It will only lock the one door, all other remain open.

So I'm thinking I need to replace the central locking unit, however here is the twist. I can use the button on the inside of the door to lock them all.
So why would the alarm and key not work, but the button will still lock the car on the inside.

Any help would be much appreciated
Jas

 

[liddell]

Oh then occasionally like tonight when I got home it works again. the alarm will lock the key will work again and when it starts to not work again, it will be alarm first then later at some point in time the key in door activation of alarm won't work.

Unlocking always remains unaffected
.

 

[liddell]

Anyone got any ideas?