U4" Malfunction Of Transmission Between Indoor Units And Outdoor Units - Daikin VRVIII-S Service Manual

SiENBE34-703
3.40 "U4" Malfunction of Transmission between Indoor Units
and Outdoor Units
U4
remote control
Display
Applicable
AII indoor unit models
Models RXYSQ4~6P
Method of
Microcomputer checks if transmission between indoor and outdoor units is normal.
Malfunction
Detection
Malfunction
When transmission is not carried out normally for a certain amount of time
Decision
Conditions
Supposed ! Indoor to outdoor, outdoor to outdoor transmission wiring F1, F2 disconnection, short circuit
Causes
! Outdoor unit power supply is OFF
! System address doesn't match
! Defect of outdoor unit PC board
! Defect of indoor unit PC board
Troubleshooting
or wrong wiring
Troubleshooting by Indication on the remote control
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