中文
含义
空调室外机冷凝器盘管温度传感器故障。E4 表示室外机盘管传感器（检测冷凝器铜管温度）检测回路开路或短路。该传感器用于室外机过热保护和制冷/制热模式下的冷凝温度监控。
常见原因
- 室外机盘管温度传感器热敏电阻损坏，阻值异常或开路/短路。
- 传感器插头松动，主板采样电压异常。
- 传感器固定位置脱落，探头未与冷凝器铜管良好接触。
- 室外机长期日晒雨淋，传感器护套老化破损进水。
- 传感器连接线在室外机内部被风扇气流带动磨损。
- 主板室外传感器信号处理电路故障。
自助排查
- 断电后打开室外机顶盖和侧面板，找到盘管传感器（通常卡在冷凝器铜管弯头处）。
- 检查传感器是否固定在铜管上——若松动脱落，重新卡回原位并确保紧密接触。
- 检查传感器导线护套是否破损，破损处用绝缘胶带包好。
- 用万用表测量传感器阻值，常温下应有一定阻值（约 5kΩ–25kΩ 视型号而定）。若为 0Ω 或无穷大则需更换。
- 传感器更换成本低且操作简单。联系 TCL 售后获取原厂配件或安排上门更换。
English
Meaning
The outdoor unit condenser coil temperature sensor has failed. E4 indicates an open or short circuit in the outdoor coil sensor (which detects condenser copper tube temperature) detection loop. This sensor is used for outdoor unit overheat protection and condensing temperature monitoring in cooling/heating modes.
Common Causes
- The outdoor coil temperature sensor thermistor is damaged — abnormal resistance or open/short circuit.
- The sensor connector is loose, causing abnormal sampling voltage at the main board.
- The sensor has fallen out of its fixed position and the probe is not in good contact with the condenser copper tube.
- Long-term sun and rain exposure has degraded the sensor’s protective sheath, allowing water ingress.
- The sensor connecting wire has been worn by airflow-driven movement inside the outdoor unit.
- The outdoor sensor signal processing circuit on the main board is faulty.
Self-Check Steps
- After powering off, open the outdoor unit top cover and side panel and locate the coil sensor (typically clipped onto a condenser copper tube bend).
- Check whether the sensor is securely attached to the copper tube — if loose or detached, clip it back into its original position ensuring firm contact.
- Inspect the sensor lead wire sheath for damage; wrap any damaged areas with electrical tape.
- Use a multimeter to measure sensor resistance; at room temperature there should be a measurable value (approximately 5kΩ–25kΩ, model-dependent). A reading of 0Ω or infinite means replacement is needed.
- Sensor replacement is low-cost and straightforward. Contact TCL after-sales for genuine replacement parts or an on-site replacement service.