Whirlpool dishwasher random heat & start

Brand:whirlpool
Model Number:wdt780saem1
Main Symptom:heat works periodically,wont work high temp or any cycle except normal, power light works randomly
What happens & when:

Error Code (if any):f7-e1
Parts or tests already tried:replaced turbitity sensor,tested thermostat, replaced door switch,replaced control board & continuity tested element & every wire in harness
Photos / video link:

Ohm out the heater instead of checking it for continuity, it should read between 8-30 ohms. With you replacing so many parts already, if it continues to act in a random pattern, I would suspect a wiring issue. I know you checked the wiring already but the inconsistent way it is still acting would lead to wiring.

tks, not wiring issue too many different things happen randomly to be a wire. already continuity tested every wire in harness.

Was the main control W10854221 replaced or was it the user control W11036550? Also, what resistance does the heating element measure? While an element can have continuity, the specific resistance would need to fall within the manufacturer’s specs or it can potentially cause issues with a control boards operation.