Midea MSH-07CRN1, MSH-07HRN1, MSH-09CRN1, MSH-09HRN1, MSH-12CRN1, MSH-12HRN1 Manual page 300

11.1.2
Display
E1
Is the LED in outdoor main PCB light?
Is the +5 voltage in outdoor main board?
Outdoor main
No8(Yellow)
Main chip(ADMCF328): between No10 and No19
Check the PC817,PC851 (indoor PCB and Outdoor main PCB)
Is PC817 or PC851 normal?
If PC817 or PC851 are defective, change indoor PCB or outdoor power PCB .
Indoor / outdoor units communication protection
No
PCB: CN5 between No7(Blue) and
Yes
Yes
LED STATUS
1. check the signal wire between, is it
connected good.
2. replace the PCB of indoor unit ,is the
unit ok?
3. replace the PCB of power supply
board ,is the unit ok?
4
299
Yes
No
Inverter module defective.
Rectifier defective