Owners/service Manual problems of the 2009 GMC Yukon Hybrid

3 of the 4 door locks failed to work as intended, I. E. , with fob and had to be manually manipulated to open doors. One door could be opened with key. One door could only be opened if lock was pulled up manually - it would lock automatically, but took manual intervention to get the lock in the un-lock position. Unless there was an adult in this position to open the lock, the door could not be accessed from the outside. This was a rear passenger door and caused great concern when children were in the car. I have had the 3 locks replaced at a great dollar cost, but could not in good conscience have children in the rear seat without having it done. I have requested reimbursement from GMC as I do not believe a 75% failure rate on door locks is acceptable safe performance of this vehicle.