This guide explains all GE Microwave error codes (CH series) with simple troubleshooting steps to help you identify and fix common issues safely before calling a technician.
F1
Touchpad Shorted
- Disconnect microwave power for 5 minutes.
- Clean keypad surface thoroughly.
- Inspect ribbon cable connection.
- Replace touchpad if buttons remain stuck.
SE
Keypad Communication Error
- Check keypad ribbon cable connection.
- Inspect control board for corrosion.
- Restart microwave after power reset.
- Replace keypad or control board if needed.
F2
Overheat Protection Triggered
- Turn off microwave immediately.
- Allow unit to cool completely.
- Check cooling fan operation.
- Inspect airflow vents for blockage.
F3
Humidity Sensor Error
- Inspect humidity sensor wiring.
- Clean sensor area inside cavity.
- Check connector for corrosion.
- Replace faulty sensor if readings are incorrect.
F4
Humidity Sensor Circuit Open
- Inspect sensor wiring for breaks.
- Test sensor continuity with multimeter.
- Reconnect loose wiring harness.
- Replace sensor if circuit remains open.
F5
Door Not Closing Properly
- Ensure door is fully closed and latched.
- Inspect door switch alignment.
- Check for debris in latch area.
- Replace door switch if defective.
F6
Relay Control Failure
- Disconnect microwave power supply.
- Inspect relay contacts on control board.
- Check for burned or damaged components.
- Replace control board if relay is faulty.
F7
Power Supply Instability
- Check outlet and circuit breaker condition.
- Avoid using extension cords.
- Test microwave on a stable power source.
- Contact electrician if voltage fluctuates.
F8
Cooling Fan Failure
- Check if cooling fan is spinning.
- Inspect fan motor wiring connections.
- Remove dust buildup around fan.
- Replace fan motor if not operating.
F9
Control Board Memory Error
- Disconnect power for 10 minutes.
- Inspect control board for moisture damage.
- Check wiring connections to PCB.
- Replace main control board if error persists.
F10
Magnetron Failure
- Stop using microwave immediately.
- Check high-voltage components.
- Inspect magnetron connections.
- Replace magnetron if defective.
F11
High Voltage Transformer Fault
- Disconnect power supply.
- Inspect transformer for burn marks.
- Check wiring and capacitor condition.
- Replace transformer if faulty.
F12
Turntable Motor Failure
- Check turntable rotation manually.
- Inspect motor coupling underneath.
- Test motor wiring connection.
- Replace motor if not rotating.
F13
Inverter Circuit Fault
- Reset microwave power supply.
- Inspect inverter board for damage.
- Check high-voltage wiring.
- Replace inverter PCB if needed.
F14
Temperature Sensor Failure
- Check sensor resistance values.
- Inspect wiring harness for damage.
- Verify sensor placement in cavity.
- Replace sensor if readings are incorrect.
F15
General System Error
- Perform full power reset.
- Check all wiring connections.
- Inspect control board for faults.
- Replace PCB if error persists.
F16
Door Interlock Switch Fault
- Check door latch alignment.
- Inspect interlock switch mechanism.
- Test switch continuity with multimeter.
- Replace door switch assembly if faulty.
F17
Humidity Sensor Drift
- Clean sensor area inside cavity.
- Check for grease or moisture buildup.
- Test sensor resistance values.
- Replace sensor if readings are unstable.
F18
Touch Panel Communication Loss
- Disconnect power for 5–10 minutes.
- Check ribbon cable connection.
- Inspect control board for corrosion.
- Replace keypad or PCB if needed.
F19
Grill Heater Failure
- Check grill element continuity.
- Inspect wiring connections for burns.
- Test heating relay operation.
- Replace grill heater if defective.
F20
Low Voltage Detection
- Check household power supply.
- Avoid using extension cords.
- Test microwave on stable outlet.
- Use voltage stabilizer if needed.
F21 / E21
Magnetron Overheat Protection
- Allow microwave to cool completely.
- Check ventilation fan operation.
- Inspect airflow vents for blockage.
- Replace magnetron if overheating continues.
F22
High Voltage Diode Failure
- Disconnect power immediately.
- Inspect high-voltage diode condition.
- Check capacitor and transformer health.
- Replace diode if shorted or open.
F23
Microwave Inverter Overload
- Reset power supply for 10 minutes.
- Check inverter board for burn marks.
- Inspect magnetron load condition.
- Replace inverter PCB if faulty.
F24
Fan Motor Speed Error
- Check cooling fan for obstruction.
- Inspect motor wiring connection.
- Test fan rotation manually.
- Replace fan motor if unstable.
F25
Internal Fuse Blown
- Disconnect microwave from power.
- Inspect internal fuse condition.
- Check for shorted components.
- Replace fuse after fixing root cause.
F26
Control Panel Moisture Damage
- Dry control panel completely.
- Inspect keypad for water intrusion.
- Check ribbon cable corrosion.
- Replace panel if unresponsive.
F27
Relay Stuck ON
- Disconnect power immediately.
- Inspect relay contacts on PCB.
- Check for burnt control board traces.
- Replace control board if relay is stuck.
F28
Sensor Calibration Error
- Reset microwave to factory settings.
- Inspect sensor mounting position.
- Check firmware or control logic.
- Replace sensor if calibration fails.
F29
General Communication Failure
- Power cycle microwave for 10 minutes.
- Inspect wiring harness connections.
- Check PCB for corrosion or damage.
- Replace main board if issue persists.