Central locking sticking Defender TD5

Hi All
I have a 2003 Defender 110 TD5. For quite some time the N/S passenger door doesn't always open with the key fob as the knob doesn't fully open; occasionally the other rear passenger door also sticks. Lately both front doors fail to open with both knobs not fully opening as are the back passenger ones meaning I have to get in using the key. They all lock fine. The key had a new battery not long ago. The main battery (red top) is only a year or two old but doesn't turn the engine that fast when really cold - sometimes I have to switch on the second (yellow top). As all four doors are playing up I assume it is not anything to do with door mechanisms so guess it is an electrical issue? Main battery?
Cheers

I have similar issues with my 2003 90, I think it is more to do with the cold temperatures and the central locking solenoid freezing up.

Probably need to take the door card off, dry it out and give it all a good spraying with oil.

You should be lucky you have central locking

I've got the same issue with mine (not central locking, but same cause I guess). I took the door card off and it seemed to be the hinged part of the lock, which i sprayed with plennty of wd40 and it fixed it, until this morning when it was off again.

It's the cold weather that affects it i think, as i had same issue last year and replaced the barrels.

I think I'll go out and put some grease on it, see if that stays around a bit better.