GE Microwave Error Code F5: Shorted Humidity Sensor... | appliancefaults.com

Technical Background:

The microwave's main control unit (MCU) monitors the humidity sensor circuit for proper resistance. A short circuit (low resistance) triggers the F5 error. The sensor typically operates on a low voltage DC circuit (5V DC). The MCU detects a voltage drop across the sensor if it's functioning correctly. A short circuit creates a direct voltage path to ground.

Symptoms:

The GE microwave displays an F5 error code and may not operate. The turntable might not spin, or the unit may shut down unexpectedly.

Possible Causes:

Shorted humidity sensor
Damaged wiring harness connecting the sensor to the control board
Defective control board (MCU)
Moisture intrusion affecting the sensor or wiring
Loose connection at the sensor or control board

Solution:

1

Disconnect power to the microwave at the breaker panel.
2

Locate the humidity sensor, typically near the exhaust vent inside the microwave cavity. You may need a 1/4-inch nut driver to remove the vent cover.
3

Visually inspect the sensor and wiring for any signs of damage, corrosion, or moisture.
4

Disconnect the sensor and use a multimeter to measure the resistance across the sensor terminals. A shorted sensor will read near 0 ohms.
5

If the sensor is shorted, replace it with a new GE-approved humidity sensor. Order from a reputable appliance parts supplier.
6

If the sensor tests good, check the wiring harness continuity from the sensor connector to the control board connector. Repair any breaks or shorts.
7

If the wiring is good and the sensor is new, the control board is likely defective and requires replacement. This is a rare case, confirm all other steps first.

Safety Warning:

Disconnect power to the microwave at the breaker panel before performing any repairs. Lockout/Tagout (LOTO) procedures should be followed to prevent accidental re-energizing. Microwave ovens contain high-voltage components that can cause serious injury or death.

Prevention:

Regularly clean the microwave interior to prevent food buildup and moisture accumulation near the humidity sensor. Avoid using excessive steam when cooking.

Expert Tip:

After replacing the sensor or control board, some GE microwave models may require a service mode reset to clear the F5 error code. Consult the service manual for the specific sequence. A common sequence is pressing and holding the 'Start' and '8' buttons simultaneously for 5 seconds.

Frequently Asked Questions

•What is the typical resistance range of a properly functioning humidity sensor in this GE microwave model?

A functioning humidity sensor typically has a resistance between 5 kOhms and 20 kOhms at room temperature (70-75°F). The resistance will vary with humidity levels.

•Where can I find the service manual for this GE microwave model to understand the exact reset procedure?

You can often find service manuals on appliance parts websites, or by contacting GE directly with the model number. Some libraries also have access to online service manual databases.

•If the wiring harness tests good, and I still get the F5 error after replacing the sensor, what other components could potentially be causing the problem?

If the wiring and sensor are good, and the F5 error persists, the MCU on the control board is the most likely culprit. However, double-check all connections and inspect the control board for any visible signs of damage, such as burnt components or corrosion, before replacing it. Some models may have a separate sensor interface board.

GE Microwave Error Code F5: Shorted Humidity Sensor Troubleshooting

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip:

Frequently Asked Questions

•What is the typical resistance range of a properly functioning humidity sensor in this GE microwave model?

•Where can I find the service manual for this GE microwave model to understand the exact reset procedure?

•If the wiring harness tests good, and I still get the F5 error after replacing the sensor, what other components could potentially be causing the problem?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Expert Tip: