Signal Transmission Error (Between Indoor Unit And Outdoor Unit) - Daikin FLKS25BAVMB Service Manual

Troubleshooting
3.6 Signal Transmission Error (between Indoor Unit and
Outdoor Unit)
U4
Remote Control
Display
Method of The data received from the outdoor unit in indoor unit-outdoor unit signal transmission is
Malfunction checked whether it is normal.
Detection
Malfunction
The data sent from the outdoor unit cannot be received normally, or the content of the data is
Decision abnormal.
Conditions
„ Wiring error
Supposed
„ Breaking of the connection wires between the indoor and outdoor units (wire No. 3)
Causes
„ Defective outdoor unit PCB
„ Defective indoor unit PCB
„ Disturbed power supply waveform
Troubleshooting
Check No.10
Refer to P.107
74
Be sure to turn off the power switch before connecting or disconnecting
Caution
connectors, or parts may be damaged.
Check the indoor unit-outdoor unit
connection wires.
Is there any wiring error?
NO
Check the voltage of the
connection wires on the indoor
terminal board between No. 1
and No. 3, and between No. 2
and No. 3.
Properly insulated?
NO
Check the LED A on the outdoor
unit PCB.
Is LED A blinking?
YES
Check No.10
Check the power supply
waveform.
Is there any
disturbance?
YES
YES
YES
∗ Before you check the LED A,
cancel the standby electricity
saving function by operating
fan operation with the remote
control.
∗ Wait at least for 7 sec. after
turning on the power.
NO
NO
SiENBE05-722_A
Correct the indoor unit-outdoor
unit connection wires.
Replace the connection
wires between the indoor
and outdoor units.
Diagnose the outdoor unit
PCB.
Replace the indoor unit PCB.
Locate the cause of the
disturbance of the power
supply waveform, and
correct it.
Service Diagnosis
(R12160)