Transmission Error (Between Microcomputers On The Outdoor Main Pcb) - Daikin VRV IV-S RXTQ-TAVJU Series Service Manual

Troubleshooting by Error Code
4.35 Transmission Error (Between Microcomputers on the
Outdoor Main PCB)
LC
Error Code
Applicable All outdoor units
Models
Method of Error Transmission conditions between microcomputers on the outdoor main PCB are tested via
Detection microcomputer.
Error Decision
No normal transmission after a certain period of time
Conditions
Supposed
Causes
Troubleshooting
187
Connection error between microcomputers on the outdoor main PCB
Defective outdoor main PCB (Transmission part)
Defective noise filter
External factors (Noise, etc.)
Defective inverter compressor
Defective fan motor
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Is the outdoor
main PCB
damaged?
NO
Inverter
compressor insulation
resistance is less than
100 kΩ.
NO
Fan motor
insulation resistance is
less than 1 MΩ.
NO
Normal monitoring
light (green) of outdoor main
PCB (A1P) blinks.
YES
Normal
monitoring light
(green) of inverter
PCB blinks.
YES
YES
YES
YES
NO
NO
SiUS331604E
Replace the outdoor
main PCB.
Replace the inverter
compressor.
Replace the fan motor.
No LC error. Check
the error code again.
Replace the outdoor
main PCB.
Keep operating.
Possibly because of
( )
sudden power failure, etc.
Service Diagnosis