Daikin SkyAir FHQ24PVJU - Power Supply Insufficient or Instantaneous Abnormality

SiUS281811EA Troubleshooting by Error Codes
Part 6 Service Diagnosis 277
4.48 Power Supply Insufficient or Instantaneous Abnormality
Error Code U2
Applicable
Models
All outdoor units
Method of Error
Detection
The main circuit capacitor voltage of the inverter and the power supply voltage is checked.
Error Decision
Conditions
The main circuit capacitor of the tested inverter has abnormal voltage or the power supply voltage
is abnormal.
Supposed
Causes
 Insufficient power supply
 Instantaneous power failure
 Defective outdoor fan motor
 Defective outdoor unit PCB