I need help

keyfob will sometimes briefly light up if i press it but nothing else happens 99% of time.. I think its managed to lock it before but unlocks straight away unlock thing before... So battery issue and some sort of wiring/solenoid issue too?

So heres what happens with a key:

-If I open drivers side with key all locks unlock.
-If I open passenger side with key only passenger side and boot unlock.

- If I open passenger side and lock passenger side it locks back up fine along with boot (although driver side never unlocked)

- If I open driver side and lock car passenger side whole car unlocks its self again.. However if I hold key in locking position then passenger side will try to unlock but then stay locked, everything else stays unlocked


To people who understand central locking systems it probably quite simple :p

I'm guessing passenger solinoid problem?? but is the solinoid part of the passenger wiring loom or what am I looking to actually buy and replace?

thanks in advance!