I'm not sure what "FDO" is. I think its a four wire connector on bottom right corner of board (white, brown, grey and white-black wires). I have 120 across brown - white, but nothing between grey-white when I run self clean. Is this the correct place to measure for voltage? I did not hear fan running on Thanksgiving when the oven went into the lock-unlock-lock issue. The micro-wave (white plastic fan) does work. Last question; can you verify the oven board part number:
Yes, knowing what to replace is the challenge. It's hard to follow the wire cause it goes to a connector in the bottom of microwave metal floor behind control panel. BUT....- I found another (single) grey wire that connects to board at "FOD" (not FDO). Its not the larger grey wire that runs to four-pin connector that had 0V. At the FOD wire connection, the voltage does read 120V when the oven starts cleaning mode (I watched it just to 120 once the door lock completes). Does this would imply I have than same problem as the previous person and the fan is bad? Could it be something else in between the board and the fan? I did check the connectors.
Ok - thanks. I guess the final test will be to look for voltage at the fan, vice at the FOD. I'll order a new fan. Thanks for the advice.