Haier 1U18TR4ERA, Service Manual

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Service diagnosis
4
4
Domestic air conditioner
10.3.10 The communication fault between indoor and outdoor
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
Supposed
■ Communication wiring disconnected.
Causes ■ The indoor PCB is broken.
■ The outdoor PCB is broken.
■ The Module PCB is broken.
Troubleshooting * Caution Be sure to turn off power switch before connect or disconnect connector, or else
parts damage may be occurred.
NO
（
A
）
Yes
NO
Yes
No
YES
Restart the a/c and it
becomes normally.
If starting up normally, but
malfunction occurs again after a
while
Check whether the linking cable
between the indoor and outdoor is well
connected or whether its core wires are
well insulated.
The outdoor mainboard needs
dehumidification.
The outdoor mainboard needs
dedust.
1. Reconnect the linking cable;
2. Replace the linking cable with new
one.