Daikin VRV RXYQ72-384XAYCA Service Manual page 344

Troubleshooting by Error Code
337
Diagnosis Flowchart-3
U7-03
Error code Sub code
(Transmission error between master
and slave 1)
The
multi transmission
wirings to multi slave 1 have
caused wiring disconnection in
them or are being
disconnected.
YES
Diagnosis Flowchart-4
U7-04
Error code Sub code
(Transmission error between master
and slave 2)
The
multi transmission
wirings to multi slave 2
have caused wiring disconnection in
them or are being
disconnected.
YES
Diagnosis Flowchart-5
U7-05
Error code Sub code
(Multi system error)
Multi outdoor unit
system?
YES
NO
NO
NO
SiUS342004EB
Replace the outdoor unit main
PCB (A1P) for multi slave 1.
Modify the outdoor unit multi
transmission wirings, and then
reset the power supply.
Replace the outdoor unit main
PCB (A1P) for multi slave 2.
Modify the outdoor unit multi
transmission wirings, and then
reset the power supply.
Replace the outdoor unit main
PCB (A1P).
Disconnect the outdoor unit multi
transmission wirings, and then
reset the power supply.
Part 6 Service Diagnosis