Midea M2OC-18HFN1-M Service Manual page 64

9.4.2.4E4(open or short circuit of outdoor temperature sensor) diagnosis and solution
F1/F2/F3/F4/F5 (open or short circuit of indoor coil temperature sensor) diagnosis and solution.
.
Error Code
Malfunction decision
conditions
Supposed causes
Trouble shooting:
Check the connections
between temperature
sensor and PCB. Are
the connections good?
Yes
Check the resistance value
of the sensor via Appendix 1
and Appendix 2
Is it normal?
No
Replace the sensor
E4/F1/F2/F3/F4/F5
If the sampling voltage is lower than 0.06V or higher than
4.94V, the LED will display the failure.
● Wiring mistake
● Sensor faulty
● PCB faulty
No Correct the connections.
Yes Replace indoor or outdoor PCB.