Error No. 05 - LG Multi V5 Service Manual

ERROR CODES

Error No. 05

Please refer to the Safety Precautions on pages 4-7 for more detail to prevent injury or death regarding the operation and service
WARNING
troubleshooting of the Multi V product.
Error No. Description
Communication
error between out-
05
door unit PCB and
indoor unit PCB.
No
Do all the indoor units
display error code CH05?
Yes
No
Is the outdoor unit
PCB LED blinking?
Yes
Check if the
communication cable is
No
properly connected
to indoor / outdoor unit
terminal blocks?
Yes
Communication from the indoor unit is normal if voltage
fluctuation (-9V ~ +9V) exists (when checking DC voltage of the
communication terminal between the indoor and outdoor units).
140
Indoor unit PCB is not receiving communica-
tions signal from outdoor unit PCB for more
than 5 minutes. Check indoor unit PCB for
issues.
After auto addressing, is
the correct number of indoor
units connected displayed?
Yes
END
Is the power supply at
the outdoor unit terminal
block correct?
Yes
Is the main circuit breaker OFF?
Yes
Power supply cable is not connected properly.
There is a problem with the main power supply.
Reconnect communication cable.
Outdoor unit PCB is malfunctioning.
Check, then replace.
Indoor unit PCB is malfunctioning.
Check, then replace.
If the DC voltage between communication terminal A, B
of indoor unit fluctuates within -9V ~ +9V, then the
communication from the outdoor unit is normal.
Due to our policy of continuous product innovation, some specifications may change without notification.
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Details
1. Auto addressing has not been performed
2. Communication cable is not connected.
3. Communication cable is short circuiting.
4. Indoor unit communication circuit error.
5. Outdoor unit communication circuit error.
6. Not enough physical distance between pow-
7. T-phase line disconnection.
Replace the PCB of indoor unit after
No
error is displayed.
Reconnect after checking the
communication cable of the indoor
unit that displays the error.
Check and replace the outdoor unit
No
PCB.
Check and replace TRANS.
Check the insulation of the inverter
No
compressor; replace if necessary.
Check the capacity of main circuit
breaker; replace if necessary.
Check the T-phase connection.
If the above are operating correctly,
turn on main circuit breaker.
Causes
properly.
er wiring and communication cables.
Images here are representative
of system components. Actual
component appearance depends
on model and system type.
See also Error Code No. 237:
RS-485 Communication Error
Between Indoor Unit and Outdoor
Unit, and Error Code No. 238:
Outdoor Unit PCB Communication
Error Between Indoor Unit and
Outdoor Unit.