Whirlpool AWZ8578 Condenser Dryer Heater TOC’S

Good afternoon,

I have a no heat problem on the above dryer, and suspect the heater, although it appears fine.

Could anyone let me know the satisfactory Ohms readings for the above dryer heater TOC’s?

Three of them giving a normal .2 to .4 Ohms resistance, though the one in the red wire circuit gives a 12k Ohms reading.

Wondering if the above is acceptable, and why four TOC’s are required?

Thank you,

jonty