中文
含义
3-2 表示洗碗机的 NTC 温度传感器（负温度系数热敏电阻）检测到短路状态。NTC 热敏电阻的正常阻值随温度升高而降低，在常温下应有数千欧姆的阻值。当主控板检测到 NTC 回路的电阻值接近零欧姆（短路）时，表明温度信号回路出现异常低阻抗。这种情况通常会导致控制板读取到极低或无效的温度数据，可能使加热器持续加热或完全不加热，影响洗涤性能并存在过热安全风险。控制板在检测到该状态后显示 3-2 错误代码。
常见原因
- NTC 传感器线束被加热器的高温管道或金属支架磨破，线芯裸露并与机器壳体搭铁短路。
- 传感器连接器内部进水或受潮，水分在插针之间形成低阻抗导电通路。
- NTC 热敏电阻本体击穿短路，内部半导体材料因过热或电压冲击而永久性失去电阻特性。
- 线束在出厂装配时被螺丝或金属卡子压伤，绝缘层和铜芯被挤压导致线与线之间短路。
- 主控板上 NTC 输入回路的贴片电容或 TVS 保护二极管击穿，造成对地短路。
- 维修操作中误将 NTC 线束端子插到错误的插座，或接线顺序颠倒。
- 温度传感器密封失效后长期浸泡在水中，传感器内部焊点之间形成电解性短路桥。
自助排查
- 断开洗碗机电源，确保完全断电后再进行后续操作。
- 拔下 NTC 传感器的连接器插头，用万用表欧姆挡直接在传感器两端子间测量电阻值：若传感器自身阻值正常（室温下约 10-12 kΩ），则短路点在传感器之外；若阻值接近零，则传感器本体已击穿需更换。
- 在传感器已拔下的状态下，用万用表测量线束端（去往主控板方向）两根导线之间的电阻值，正常应为无穷大；若测得低阻值，说明线束内部或控制板存在短路。
- 沿 NTC 线束全程检查，重点查看线束穿过金属板孔洞的位置、经过加热器外壳的位置，寻找绝缘皮破损、熔化或铜芯外露的痕迹。
- 检查 NTC 连接器插头的塑料外壳是否有裂纹、进水或受潮迹象，必要时用吹风机低温挡吹干连接器内部。
- 若线束和传感器均正常但线束端仍测得短路，拔下主控板上 NTC 对应的接插件后再次测量线束：若短路消失则问题在主控板本身。
- 主控板相关故障需要专业检测设备排查，建议联系肯摩尔授权维修人员进行板级诊断和维修。
English
Meaning
3-2 indicates that the dishwasher’s NTC temperature sensor (Negative Temperature Coefficient thermistor) is detected as shorted. The NTC thermistor’s normal resistance decreases as temperature rises and should read several thousand ohms at room temperature. When the control board detects near-zero resistance (shorted) on the NTC loop, it indicates an abnormally low impedance in the temperature signal circuit. This condition typically causes the control board to read extremely low or invalid temperature data, which may result in the heater running continuously or not at all, affecting wash performance and posing an overheating safety risk. The control board displays the 3-2 error code upon detecting this condition.
Common Causes
- The NTC sensor wiring harness has been chafed by the heater’s hot tubing or metal brackets, exposing bare wire that shorts to the appliance chassis ground.
- Water or moisture has entered the sensor connector housing, creating a low-impedance conductive path between the pins.
- The NTC thermistor body has suffered a breakdown short — the internal semiconductor material has permanently lost its resistive properties due to overheating or voltage surge.
- The wiring harness was pinched by a screw or metal clip during factory assembly, crushing the insulation and copper conductors together causing an inter-wire short.
- The SMD capacitor or TVS protection diode on the main control board’s NTC input circuit has failed short, creating a short to ground.
- During a previous repair, the NTC harness terminals were mistakenly plugged into the wrong socket, or the wiring sequence was reversed.
- After the temperature sensor’s seal failed, the sensor was submerged in water for an extended period, forming an electrolytic shorting bridge between internal solder joints.
Self-Check Steps
- Disconnect the dishwasher from power and ensure it is completely de-energized before proceeding.
- Unplug the NTC sensor connector and use a multimeter in ohms mode to measure the resistance directly across the two sensor terminals. If the sensor’s own resistance reads normal (~10–12 kΩ at room temperature), the short lies outside the sensor. If the reading is near zero, the sensor body itself has failed and needs replacement.
- With the sensor still unplugged, measure the resistance between the two wires on the harness side (going toward the control board). A normal reading should be infinite; a low resistance reading indicates a short within the harness or on the control board.
- Inspect the entire length of the NTC wiring harness, paying special attention to points where the harness passes through metal panel holes and near the heater housing, looking for signs of damaged, melted insulation or exposed copper conductors.
- Check the NTC connector’s plastic housing for cracks, water ingress, or moisture. If necessary, use a hair dryer on the low heat setting to thoroughly dry the interior of the connector.
- If both the harness and sensor test normal but the harness side still measures shorted, unplug the NTC connector from the main control board and re-measure the harness. If the short disappears, the fault is on the control board itself.
- Control board faults require specialized diagnostic equipment. It is recommended to contact a Kenmore authorized service technician for board-level diagnosis and repair.