Daikin RXQ12AHR Service Manual page 273

SiAF341904E
Troubleshooting
Part 6 Service Diagnosis
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Check for details of error in
monitor mode.
U4-01
YES
Has the
indoor or
outdoor unit PCB
been replaced, or has
the indoor-outdoor or
outdoor-outdoor
transmission
wiring been
modified?
NO
Do all
indoor unit
remote controllers in
the same refrigerant
system display
U4?
YES
Reset the power supply once.
Does the
microcomputer
normal monitor indication
lamp (HAP) on the
outdoor unit main
PCB blink?
YES
Does the
seven-segment display
show (1) or (2)?
( 1)
YES
The lamp
does not turn OFF
for a period of 12 minutes
or more.
NO
Are the
indoor-outdoor and
outdoor-outdoor transmission
wirings normal?
YES
Disconnect the
outdoor-outdoor
transmission wiring.
Does the system normally
operate with a single
transmission
line?
YES
NO
YES
Are the
indoor-outdoor and
NO
outdoor-outdoor
transmission wirings
normal?
NO
Is voltage
between L1 and N
NO
terminals of the outdoor unit
PCB 380 to 415 V?
YES
Fuse on the
NO
outdoor unit main PCB
has blown out.
NO
YES
NO
NO
Troubleshooting by Error Code
Go to the next page.
U4-03
(Indoor unit system
transmission error)
Press and hold RETURN
(BS3) on the master outdoor
unit main PCB (A1P) for a
period of 5 seconds or more.
(The system will not operate
for a period of 12 minutes at
maximum.)
YES
Replace the indoor unit PCB.
Modify the transmission
wirings.
Correct the voltage.
1 :OFF
:ON :BLINK
NO
(1)
SEG1 SEG2 SEG3
(2)
YES
Replace the fuse.
Replace the outdoor unit
main PCB (A1P).
Press and hold RETURN
(BS3) on the outdoor unit
main PCB (A1P) for a period
of 5 seconds or more.
Modify the transmission
wirings.
Replace the outdoor unit main
PCB (A1P).
Mount the DIII-NET extension
adaptor.
267