SiUS371901E
Troubleshooting by Error Code
Service Diagnosis
342
3.63 Power Supply Insufficient or Instantaneous Abnormality
Error Code
U2
Applicable
Models
All outdoor unit models
Method of Error
Detection
Detect the voltage of capacitor of the main circuit in the inverter PCB.
Error Decision
Conditions
When the voltage in the DC circuit (between diode module and power module) falls below 190 VDC
(for 208/230 V models), 380 VDC (for 460 V models) or 560 VDC (for 575 V models).
Supposed
Causes
Abnormal power supply voltage
Instantaneous power failure
Open phase
Defective inverter PCB
Defective outdoor unit main PCB
Defective compressor
Defective main circuit wiring
Defective fan motor
Defective connection of signal cable
Troubleshooting
There are
some defects in the
power supply conditions
aforementioned.
The insulation
resistance of the
compressor is not more
than 100 k
Ω
.
NO
YES
YES
Fix the defects.
Replace the compressor
(M1C).
Check for power supply
conditions.
(1) Power supply voltage falls
within ±10% of the rated
voltage?
(2) Any open phase in the
power supply wiring or any
wrong wiring?
(3) Imbalance in the power
supply voltage is
maintained within 12 V?
A
NO
Caution
Be sure to turn off the power switch before connecting or disconnecting
connectors, or parts may be damaged.
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Summary of Contents for REYQ72-456XATJU
Page 415: ...SiUS371901E Wiring Diagrams Appendix 402 REYQ144 168XATJU 2D119206A ...
Page 416: ...Wiring Diagrams SiUS371901E 403 Appendix REYQ72 96 120XAYDU 2D119207B ...
Page 417: ...SiUS371901E Wiring Diagrams Appendix 404 REYQ144 168XAYDU 2D119208B ...
Page 418: ...Wiring Diagrams SiUS371901E 405 Appendix REYQ72 96 120 144 168XAYCU 2D119209A ...
Page 421: ...SiUS371901E Wiring Diagrams Appendix 408 FXZQ05 07 09 12 15 18TAVJU 3D110443A ...
Page 423: ...SiUS371901E Wiring Diagrams Appendix 410 FXEQ07 09 12 15 18 24PVJU 3D098557A ...
Page 426: ...Wiring Diagrams SiUS371901E 413 Appendix FXMQ07 09 12 15 18 24 30 36 48 54PBVJU 3D093209B ...
Page 428: ...Wiring Diagrams SiUS371901E 415 Appendix FXHQ12 24 36MVJU 3D048116C ...
Page 429: ...SiUS371901E Wiring Diagrams Appendix 416 FXAQ07 09 12 18 24PVJU C 3D075354D ...
Page 435: ...SiUS371901E Wiring Diagrams Appendix 422 VAM1200GVJU 3D073270D ...
Page 437: ...SiUS371901E Wiring Diagrams Appendix 424 1 4 2 Multi Branch Selector Unit BS4Q54TVJ 3D089123B ...
Page 438: ...Wiring Diagrams SiUS371901E 425 Appendix BS6 8Q54TVJ 2D089122B ...
Page 439: ...SiUS371901E Wiring Diagrams Appendix 426 BS10 12Q54TVJ 2D089121B ...
Page 440: ...Revision History Month Year Version Revised contents 04 2019 SiUS371901E First edition ...