GREE         U-Match 5 SERIES UNIT SERVICE MANUAL 
66 
Troubleshooting: 
Malfunction of 
condenser 
temperature 
sensor
Check if the condenser 
temperature sensor on 
mainboard is inserted on the 
needle stand correctly
Disconnect 
the temperature sensor and 
measure if its resistance is 
normal
Correctly insert the 
temperature sensor 
on the needle stand
Replace the 
temperature sensor
Replace the 
outdoor 
mainboard
Yes
No
No
Yes
 
Note: Please refer to Appendix 1 for the relation between temperature and resistance of temperature sensor. 
3.4.11 “F3” Outdoor Ambient Temperature Sensor Error 
Error display: ODU mainboard, IDU wired controller and IDU receiver light board will display:F3   
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