Hi.
You need to determine if the problem is the hi - limit switch, motor or the control board.
Remove the top (3 screws at the back slide and lift up), Locate the main control board
Part number: WE4M488
When the dryer fails and stops use the multimeter to check if there is 120VAC at the 3 wire plug OR(3) and WH(2). If the voltage is present - the hi-limit is open and you should check the entire air flow system for restrictions.
If not - move to the 4 wire plug and check for 120VAC from PURP(3) to Brown/Yellow(2).
If the voltage present - most likely it's the bad motor.
If no voltage - bad control board.
The motor
Part number: WE17M42
The hi-limit
Part number: WE4M137
Here are the breakdown diagrams and
Controls & Backsplash parts for GE DBVH512EF0WW - AppliancePartsPros.com
Simon.