One problem related to door latch has been reported for the 2009 Volvo C70. The most recently reported issues are listed below.
Driver door unlatches without warning; interior lights illuminated. Door moves/opens about 1/4-1/2 inch but safety catch prevents full opening. Driving over smooth road, top down. No highway or surface interruptions (such as bumps or holes) that jarred door open. Same events has happened about 8-10 separate times. Dealer reports no codes captured and unwilling to replace door lock assembly.