37
Troubleshooting
Diagnostic procedure for check code
Check code Status of air conditioner Operation cause
[04] Outdoor unit stops 1. Wiring fault between indoor and Multi
Inverter serial signal Indoor unit fan continues Controller or Multi Controller and outdoor
short circuit interface PC board.
Inter-unit communication 2. Defective communication PC board.
3. Defective IPDU PC board.
4. Noise from outside.
5. High level refrigeration leak (RBC-RD2-PE).
Is there continuity of the
communication cable between
the indoor unit and Multi
Controller?
Replace communication cable
h
j
Ye s
No
Is there continuity of the
communication cable between
the Multi Controller the outdoor
unit
Replace communication cable
h
No
Is there continuity of the
communication cable between
the outdoor interface PC board
and outdoor IPDU PC board?
Replace communication cable
h
No
Is there voltage present
between pins 4 and 5 of CN1
on communication PC board?
(DC 0 to 5 V, pin 5-GND)
Communication PC board is defective - replace
h
No
Is there voltage present
between pins 3 and 5 of CN1
on interface PC board?
(DC 0 to 5 V, pin 5-GND)
IPDU PC board is defective - replace
h
No
j
Ye s
j
Ye s
j
Ye s
j
Ye s
Check noise interference from
outside, etc.
j
Ye s
Is refrigerant detector
RBC-RD2-PE fitted?
Complete checks detailed above
h
No
j
Ye s
Are the high level alarm and
the shutdown LEDs on the
RBC-RD2-PE (RED) on?
Complete checks detailed above
h
No
j
Ye s
Refrigerant leak.
Leak-check unit.