The electrical lock/unlock functions work fine when I push either the lock or unlock buttons. When I pull on the door handle to open the side door, from inside the van or outside the van, nothing happens, in other words the opening mechanism doesn't move. I suspect a linkage problem from the handle to the bolt/latch I guess, but it looks like special tools are needed to access the guts of the door handle/lock/mechanism assembly. Should I surrender and call or visit a lock specialist or repair shop or is there a simple DIY to get in and fix it? And can you tell me what the usual problems could be? Is it expensive to have fixed?