GREE         U-Match 5 SERIES UNIT SERVICE MANUAL 
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3.4.8 “F0” Indoor Ambient Temperature Sensor Error 
Error display: IDU wired controller and IDU receiver light board will display F0 
Error judgment condition and method: 
Sample the AD value of temperature sensor through temperature sensor detecting circuit and judge the 
range of AD value, If the sampling AD value exceeds upper limit and lower limit in 5 seconds continuously, report 
the error. 
Possible reason: 
■Poor contact between ambient temperature sensor and terminal in mainboard interface 
■Ambient temperature sensor is abnormal 
■Detecting circuit is abnormal 
Troubleshooting: 
 
3.4.9 “F1” Evaporator Temperature Sensor Error 
Error display: IDU wired controller and IDU receiver light board will display F1 
Error judgment condition and method: 
Sample the AD value of temperature sensor through temperature sensor detecting circuit and judge the 
range of AD value, If the sampling AD value exceeds upper limit and lower limit in 5 seconds continuously, report 
the error. 
Possible reason: 
■Poor contact between temperature sensor and terminal in mainboard interface 
■Temperature sensor is abnormal 
■Detecting circuit is abnormal