
SiMT041311E
Troubleshooting
Service Diagnosis
174
Troubleshooting
YES
(R19686)
Caution
Check the power supply voltage.
Check indoor unit also, because a communication circuit fault
may be caused by the problem related to the indoor unit.
NO
NO
Are the
connecting wires on
the terminal board properly
connected?
YES
NO
Check the varistor on the outdoor
unit PCB.
Burst?
YES
YES
Check the fuse on the outdoor
unit PCB.
Does the fuse have
continuity?
NO
YES
Wait more than 10 seconds.
Check the thermal fuse on the
terminal board of the outdoor
unit.
Does the thermal fuse
have continuity?
YES
Go to the next page.
NO
5 V ± 0.5 V
NO
Check +5V and GND on the
outdoor unit PCB.
Turn the power on again.
Start fan operation with the
remote controller.
Is the
power supply voltage
fluctuation within ±10% from
the rated value?
Correct the power supply.
Replace the varistor.
Replace the fuse.
Reconnect the wire
properly. Replace the
terminal board. Replace the
thermal fuse on the terminal
Replace the outdoor unit
PCB.
Replace the thermal fuse
on the terminal board.
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
NO
YES
Check if the unit is earthed.
Earth the system.
Earthed?
∗
Cancel the standby electricity
saving function by starting fan
operation with the remote controller.