Central locking won't lock and/or unlock Citroën C5 2001?

[james125]

Hello all.

Just acquired a Citroen C5 of my father, he gave me it as I bought him a new one....something wrong about that.

Anyway the problems with the door locks are as follows;

Nearside front doesn't lock
Nearside rear sometimes stays locked - not that this is a major concern...-Apparently opening doors is a new requirement coming to the MOT so maybe it is?
Offside front (drivers door) locks and unlocks perfectly
Offside rear doesn't lock

All the pins sound like they move when I turn the key, so I'm really unsure if what's going on.

-Also the remote central locking doesn't work, not really important but would be nice to do, is it easy to replace batteries?

Thanks again!