Volvo: Door Lock Linkage, linkage problem, locks

Question
My passenger door will not lock even though the manual push lock goes down when activating the power lock.  All other doors lock.  When pushing down the manual lock, there is no resistance like on the other door manual locks.  I was told this is a linkage problem.  What is the linkage (a spring, a link, a rod), how much time does it take to repair, how difficult is it, and what is the cost of the parts to repair.

Answer
Holly,
Linkage could be a rod, clip, spring or pin yes. Time to fix is about 1 to 2 hours, not counting the possibility of ordering of parts. How hard is the repair, not bad, just need some patients and good light to see what and where the problem is at. Cost is about $100.00. That would be labor and a small parts, more parts needed the cost goes up.