Joe G Sandy Springs , GA May 26, 2015 Appliance: Bosch WTA3500 UC/04 Dryer turns on but would not start drying cycle Installed new door latch mechanism. If your Bosch WTA3510 turns on but then just sits there and won't start drying, this could be the problem. 2 People found this story helpful Do-It-Yourself Rating: Repair Time Estimate: 15-30 minutes