Our 2005 G Vitara has had sporadic problems with remote locking for the last 12 months or so,sometimes it would work and sometimes not.
It refused to unlock/lock at all yesterday and the remote batteries were ok voltage wise.
So I had a quick look around on here at some older posts and realised that the simplest fault would be if the drivers 'door closed' switch was not working,so I opened the door - 'sho nuff' the interior light did not illuminate.
I unshipped the switch and cleaned up the screw and switch body to get a good earth,yep that fixed the fault but just as I was clearing up the removed corrosion dust from the switch - it came unplugged from the loom plug - hell - absolutely no spare wire so that I could plug in again.
Long story short I had to undo the lower seatbelt mounting bolt - remove a few plastic fasteners and lever the trim panel out of the way - not an easy job on a cold scottish day on a 3 door vitara as the trim is one piece back to the tailgate.
The plastic was hard and brittle because of the low ambient temp and I had to be real careful not to damage it (would have been much more pliable on a warm day),but I did it in the end and locking restored to full function.