Microwave shows F5 and will not start or stops shortly after starting.

Safety first: Unplug the microwave. High-voltage components can be lethal; do not attempt live testing unless you are a trained technician.

• Reset the control: Disconnect power for 10–15 minutes, then reconnect and test a short cook cycle.
• Listen for relays: When pressing START, listen for a click from the control board area. No click or repeated clicking may indicate a relay issue.
• Visual inspection: Remove the outer cabinet and inspect the main control board for burnt spots, cracked solder joints, or melted relay cases.
• Check for obvious shorts: Look for burnt wiring near the high-voltage transformer, capacitor, or magnetron that could overload the relay.
• Replace control board: In most cases, F5 requires replacing the main control board (PCB). Ensure you order the correct Hotpoint part number for your model.
• Professional service: Because this fault may involve high-voltage components, consider having a qualified technician confirm that the magnetron and transformer are not shorted before installing a new board.