Set the timer to Timed-regular. The followed contacts should be closed: BK-BU, T-W, TM-OR.
Also, when the start switch is pressed the two blue wires contacts should have continuity (closed).
You can also check the motor by applying 120VAC directly to 4M and 5M motor contacts.
Here are the breakdown diagrams and Cabinet parts for Roper RGS6745PQ0 - AppliancePartsPros.com
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