Sinclair SDV 6 Service Manual page 111

Error display
Error impact
Error trigger
Error recovery
Possible cause
Troubleshooting
108
Digital display
The faulty IDU stops. Other IDUs of the same system: operate normally.
ODU of the same system: operate normally.
 Power supply voltage is below the programmed protection threshold (165V)
 Automatic recovery
 Power supply voltage is lower than 165V
 Indoor unit fan driver board is damaged
Use a multimeter to check
whether the power supply voltage of
the indoor unit is lower than 165V
Rectify the power supply
P52
YES
Display position
Panel, display box, and wired controller
Replace the fan drive
board or main control
No
board