Hi, is anyone familiar with VH to early VK door lock mechanisms? My VK model has the push-pull lock knob on top of the door. You know how it is supposed to make a positive click up and down and stay there... well my problem is that mine doesn't do that anymore on driver door and is loose, nothing to hold it up or down, no positive action. I had a good look inside both front door latch and lock areas (passenger side is ok) to see if I could see what is broken or missing (eg a spring) but I can't see anything at all. Would appreciate if anyone knows what I have to replace or fix , thanks.