中文
含义
5H 表示主控板检测到水温传感器（热敏电阻）信号异常：读数超出合理范围、开路或短路。通用电气洗碗机在洗涤泵出口或集水槽区域安装了一个 NTC 热敏电阻（通常 10 kΩ @ 25°C），主控板通过分压电路读取其阻值并换算为水温。当主控板检测到阻值对应温度持续低于 -10°C 或高于 100°C（等效开路或短路），系统判定传感器回路故障，显示 5H 代码。虽然机器仍可能继续运行，但无法正确控制加热，洗涤和干燥效果将受影响。
常见原因
- 热敏电阻探头本身老化或受潮后参数漂移，常温下阻值大幅偏离标称值，主控板读取的温度值与实际水温不符。
- 温度传感器线束连接器插头松动、进水氧化导致端子间接触电阻增大，分压信号失真。
- 传感器至主控板的信号线束在沿水槽底部的布线路径中被磨损、挤压或老鼠咬断，信号线断开或对地短路。
- NTC 热敏电阻受水垢完全包裹，导热受阻，传感器读数滞后严重，主控板判断为传感器响应异常。
- 主控板上温度检测电路的分压精密电阻损坏或 ADC 通道静电击穿，即使传感器正常也无法正确采样。
自助排查
- 将洗碗机断电 5 分钟让主板完全复位，重新通电后运行一个不带加热的短程序（如快速漂洗），观察 5H 代码是否仍出现：偶发代码可能因湿度引起的瞬时短路，干燥后可自愈。
- 断电后拆下下前面板，沿着水槽底部找到温度传感器（通常为一个带两根线的塑料探头组件，用螺丝或卡扣固定在水槽上），查看传感器本体和接头是否有水渍、锈蚀或绿色铜锈。
- 拔下传感器连接器插头，检查公母端子是否有白色或绿色氧化物：如有，用电器接点清洁剂喷涂并反复插拔数次清除氧化层。
- 如有万用表，在环境温度下（记下当前室温）测量热敏电阻两端阻值，与标称值对比：10 kΩ 型在 25°C 时约 10 kΩ，在水龙头冷水（约 15°C）中应约 15-16 kΩ。若测得 0 Ω（短路）或 OL（开路），传感器已损坏需更换。
- 检查传感器周边水槽是否有积垢：大量水垢将传感器探头整个包裹会影响感温，清理水垢后复查。
- 若传感器阻值正常、接头清洁牢固仍报 5H，需联系通用电气售后检测主控板温度采样电路。
English
Meaning
5H indicates that the main control board has detected an abnormal water temperature sensor (thermistor) signal: the reading is outside the plausible range, open circuit, or short circuit. GE dishwashers have an NTC thermistor (typically 10 kΩ @ 25°C) installed at the wash pump outlet or in the sump area; the control board reads its resistance through a voltage divider circuit and converts the value to water temperature. When the control board detects that the resistance corresponds to a temperature consistently below –10°C or above 100°C (equivalent to an open or short circuit), the system identifies a sensor loop fault and displays code 5H. While the machine may continue to run, it cannot correctly control heating, and both wash and dry performance will be affected.
Common Causes
- The thermistor probe itself has aged or absorbed moisture, causing parameter drift; its resistance at room temperature deviates significantly from the nominal value, so the temperature read by the control board does not match the actual water temperature.
- The temperature sensor wiring harness connector plug is loose or has suffered water ingress and oxidation, causing increased contact resistance between terminals and a distorted voltage-divider signal.
- The signal wiring harness from the sensor to the main control board has been abraded, pinched, or rodent-damaged along the tub bottom routing path; the signal wire is broken or shorted to ground.
- The NTC thermistor is completely encased in scale, blocking heat conduction and causing severe sensor reading lag; the control board interprets this as a sensor response anomaly.
- The precision voltage-divider resistor in the temperature detection circuit on the main control board has failed, or the ADC input channel has suffered ESD damage, preventing correct sampling even if the sensor is normal.
Self-Check Steps
- Disconnect the dishwasher from power for 5 minutes to allow the control board to fully reset; restore power and run a short non-heated cycle (such as Quick Rinse) and observe whether code 5H reappears. Intermittent codes may be caused by moisture-induced transient shorts that self-resolve once dry.
- With power disconnected, remove the lower front panel, trace along the tub bottom to locate the temperature sensor (typically a plastic probe assembly with two wires, screwed or clipped onto the tub), and inspect the sensor body and connector for water stains, rust, or green copper corrosion.
- Unplug the sensor connector and inspect the male/female terminals for white or green oxide deposits; if present, spray with electrical contact cleaner and plug/unplug several times to clear the oxidation layer.
- If you have a multimeter, measure the thermistor resistance at ambient temperature (note the current room temperature) and compare against the nominal value: a 10 kΩ type should read approximately 10 kΩ at 25°C, and about 15–16 kΩ in cold tap water (~15°C). A reading of 0 Ω (short) or OL (open) means the sensor has failed and requires replacement.
- Check for scale buildup around the sensor on the tub: heavy scale fully encasing the sensor probe impairs temperature sensing; clean the scale and recheck.
- If the sensor resistance is normal and the connector is clean and secure but code 5H persists, contact GE after-sales service to diagnose the control board temperature-sampling circuit.