Dryer stops mid-cycle (Model DPVH880GJ0WW )

Dryer runs for about 15min and then stops with the start/stop light flashing. After 20min I can then restart but it will run for less time than when first started up. It does this even on the Air fluff cycle (No heat).

I have:
Cleaned the vent/exhaust
Checked the service mode for error codes - there are none
Replaced both the flame sensor and ignitor
Replaced the control board

I am beginning to think there is a thermal sensor in the motor that trips but the schematics don't show this.

All help appreciated.

DS

Have you disassembled it and cleaned it yet? Most likely it's dirty. This also applies to the motor. If the motor is full of dirt it will overheat. Why did you replace the control board? Did you test anything to come to the conclusion that it was bad?Who makes this dryer? Attached are some manuals:https://dl.dropboxusercontent.com/u/8010163/Whirlpool%20Dryers.zip
https://dl.dropboxusercontent.com/u/8010163/GE%20Dryer%20%20Manuals.zip
https://dl.dropboxusercontent.com/u/8010163/Maytag%20Dryers.zip
https://dl.dropboxusercontent.com/u/8010163/Kenmore%20Dryer%20Manuals.zip