Outdoor Unit Pcb Abnormality Or Signal Transmission Circuit Abnormality - Daikin D Series Service Manual

SiBE12-519
4.23 Outdoor Unit PCB Abnormality or Signal Transmission
Circuit Abnormality
U4
Remote
Controller
Display
Method of The data received from the outdoor unit in indoor unit-outdoor unit signal transmission is
checked whether it is normal.
Malfunction
Detection
Malfunction When the data sent from the outdoor unit cannot be received normally, or when the content of
the data is abnormal.
Decision
If the indoor unit cannot communicate with the outdoor unit for 15 seconds, the system will be
Conditions
shut down.
Supposed
Causes
Troubleshooting
Service Diagnosis
Faulty outdoor unit PCB.
Faulty indoor unit PCB.
Indoor unit-outdoor unit signal transmission error due to wiring error.
Indoor unit-outdoor unit signal transmission error due to breaking of wire in the connection
wires between the indoor and outdoor units (the transmission wire).
Be sure to turn off power switch before connect or disconnect connector,
Caution
or parts damage may be occurred.
Check the indoor unit-outdoor unit
connection wires.
Is there any wiring error?
NO
Fully insulated?
ex. between wirings, earth.
Fine
The connection wiring
length over 30m?
NO
Check the outdoor unit's LED A.
Is LED A flashing?
YES
Disconnect the No.3 terminal.
Check the voltage of the indoor
unit-outdoor unit connection wires
between No.2 and No. 3. (Touch
the No.2 termintal with (-) in DC
range)
Is the voltage 30~50V?
NO
YES
Not enough
YES
NO
YES
Troubleshooting
Correct the indoor unit-outdoor
unit connection wires.
Replace the connection wirings.
Carry out the wiring work
within the regulation.
(less than 30m)
Replace the outdoor unit PCB.
Replace the indoor unit PCB.
Replace the outdoor unit PCB.
(R3046)
169