中文
含义
F3 表示微波炉湿度传感器（蒸汽传感器）开路或短路故障。湿度传感器安装在微波炉排气通道内，用于自动烹饪（传感器烹饪）模式下检测食物释放的蒸汽量以自动控制加热时间。传感器实质为压电式或电阻式湿敏元件，信号经放大电路送入控制板 ADC 通道。当控制板检测到传感器信号电压持续超出正常范围时，判定传感器故障并显示 F3。此故障不影响手动定时加热模式，但所有传感器自动烹饪模式将不可用。
常见原因
- 传感器探头表面被长期积存的油污覆盖，湿敏层无法接触蒸汽，等效于开路。
- 传感器内部湿敏电阻或压电晶片因高温老化而失效，输出信号漂移或消失。
- 传感器与控制板之间的信号线束连接器因振动松脱或端子氧化。
- 排气通道堵塞，蒸汽无法到达传感器探头位置。
- 控制板上传感器信号调理电路的运算放大器损坏。
自助排查
- 拔掉微波炉电源插头。找到湿度传感器的位置——通常位于控制面板后方或顶部排风口附近。拔下传感器插头，用万用表测量传感器两端引脚阻值。阻值应落在数据手册指定范围内（通常在几 kΩ 到几百 kΩ 之间）；若为无穷大或零，则传感器本身损坏。
- 检查传感器探头表面。如有可见油污，用棉签蘸少量异丙醇（IPA）轻轻擦拭传感器感湿面。待完全挥发后再插回测试。
- 检查微波炉顶部和侧面的排气口是否有积灰堵塞，确保蒸汽可以畅通排出。
- 检查传感器线束与控制板的连接插头是否牢固插入。如有氧化，用电子清洁剂处理。
- 如果传感器及连接均正常但仍显示 F3，故障位于控制板上的传感器接口电路。湿度传感器故障通常不影响手动微波加热功能，可继续使用手动模式。如需修复自动烹饪功能，联系 GE 售后更换湿度传感器或控制板。
English
Meaning
F3 indicates an open or short circuit in the microwave humidity sensor (steam sensor). The humidity sensor is mounted in the microwave exhaust duct and is used in automatic cooking (sensor cooking) modes to detect the amount of steam released by food and automatically control the heating duration. The sensor is essentially a piezoelectric or resistive humidity-sensitive element whose signal passes through an amplifier circuit to the control board’s ADC input. When the control board detects that the sensor signal voltage is persistently outside the normal range, it declares a sensor fault and displays F3. This fault does not affect manual timed heating mode, but all sensor-based automatic cooking modes become unavailable.
Common Causes
- The sensor probe surface is coated with long-term oil and grease buildup, preventing the humidity-sensitive layer from contacting steam — effectively an open circuit.
- The internal humidity-sensitive resistor or piezoelectric crystal has aged and failed due to high temperature, causing signal drift or dropout.
- The signal harness connector between the sensor and control board has loosened from vibration, or the terminals are oxidized.
- The exhaust duct is blocked, preventing steam from reaching the sensor probe location.
- The operational amplifier in the sensor signal conditioning circuit on the control board is damaged.
Self-Check Steps
- Unplug the microwave. Locate the humidity sensor — usually behind the control panel or near the top exhaust vent. Unplug the sensor connector and measure the resistance across the sensor pins with a multimeter. The resistance should fall within the datasheet-specified range (typically a few kΩ to a few hundred kΩ); an infinite or zero reading indicates the sensor itself is damaged.
- Inspect the sensor probe surface. If visible grease is present, gently wipe the humidity-sensitive surface with a cotton swab moistened with isopropyl alcohol (IPA). Allow it to fully evaporate before reconnecting and testing.
- Check the top and side exhaust vents of the microwave for dust buildup or blockage to ensure steam can exit freely.
- Verify the sensor harness connector is firmly plugged into the control board. If oxidation is present, treat the terminals with electronic contact cleaner.
- If the sensor and connections are intact but F3 persists, the fault lies in the sensor interface circuit on the control board. A faulty humidity sensor generally does not affect manual microwave heating, so manual mode can still be used. To restore automatic cooking, contact GE service to replace the humidity sensor or control board.