Switches Off half way through a run and few mins later turns back On
"Hi @sri_yj ,
Without access to the service manual it would be very difficult.
Also mostly these days it is usually a case of installing a replacement part to see if it works and the faulty board is returned for repair or it could even be disposed of as it is cheaper to manufacture new boards than it is to find and fix the problems in faulty boards.
You could always check what the return policy is from the parts supplier and take a chance on getting the correct board the first time, if the price was OK that is to return it if it wasn't the right one. Just a thought.
If you do decide to do this, lookup ""how to discharge a capacitor in a microwave oven"" before you get to deep into the repair. Depending on your medical condition microwave ovens can still be lethal or give a nasty shock even if the power has been totally disconnected for days."