Washer-dryer combo will not start any cycle; display shows F01 shortly after pressing Start.

Safety first: Unplug the JennAir combo from the wall outlet or switch off the dedicated breaker before any inspection. Do not work on live circuits.

• Power reset: Disconnect power for 5 minutes, then restore power and try a short cycle. Sometimes the control locks up after a surge.
• Check outlet and supply: Verify the outlet has 120V (or local spec) using a meter, and that the plug is fully seated. Inspect the power cord for burns or cuts.
• Inspect control board connections: Remove the top or rear access panel (per JennAir service manual). Locate the main control board (CCU). Reseat all harness connectors one at a time, ensuring they are fully latched and free of corrosion or burnt pins.
• Look for visible board damage: Check for burnt spots, bulging capacitors, or melted solder joints. Any visible damage usually means the board must be replaced.
• Replace the CCU if needed: If F01 returns immediately and wiring is sound, replace the main control board with the correct JennAir part number. Transfer each connector to the new board one at a time to avoid miswiring.

When to call a technician: If you are not comfortable testing live voltage or replacing electronic boards, contact a qualified appliance technician.