Haier 1U50MERFRA-4 Service Manual page 45

10.4.10 The communication fault between indoor and outdoor
Split board
Indoor display E7 outdoor display LED1 flash 15 times
Method of
Communication is detected by checking the indoor PCB and the outdoor PCB.
Malfunction
Detection
Malfunction The outdoor PCB broken leads to communication fault.
Decision The indoor PCB broken leads to communication fault.
Conditions
 Communication wiring disconnected.
Supposed
 The indoor PCB is broken.
Causes
 The outdoor PCB is broken.
 The Power Module is broken.
* Caution: Be sure to turn off power switch before connect or disconnect connector,
Trouble
or else parts damage may be occurred.
shooting
Is it normal after restart
the AC?
NO
If starting up
normally, but
malfunction occurs
again after a while
YES
Check whether the linking cable
between the indoor and outdoor
is well connected or whether its
core wires are well insulated or
its L/N is not reversed.
YES
YES
The outdoor PCB needs
dehumidification
NO
The outdoor PCB needs
dust
Reconnect the
NO
connecting
cable or replace
with a new one.
43
Service Diagnosis