Signal Transmission Error Between Indoor Unit And Outdoor Unit In The Same System - Daikin RMXS-L Series Service Manual

Troubleshooting for Outdoor Unit
7.27 Signal Transmission Error between Indoor Unit and
Outdoor Unit in the Same System
U9
Error Code
Method of Error
Detection
Error Decision
Conditions
Supposed
Causes
Troubleshooting
Turn on all indoor units.
256
Signal transmission error within system
Defective electronic expansion valve in indoor unit of other system
Defective indoor unit PCB in other system
Improper connection of transmission wiring between indoor and outdoor unit
Be sure to turn off the power switch before connecting or disconnecting
Caution
connectors, or parts may be damaged.
U9
has
YES
been displayed for 2
minutes or more?
NO
UA
blinks on the
YES
other remote controllers
within the same
system?
NO
A1
blinks on the
YES
other remote controllers
within the same
system?
NO
A9
blinks on the
YES
other remote controllers
within the same
system?
NO
U4
blinks on the
YES
other remote controllers
within the same
system?
NO
SiUS181631EA
Re-diagnose by display after
passage of 2 minutes or
more.
Refer to troubleshooting for
UA
error code.
Refer to troubleshooting for
A1
error code.
Refer to troubleshooting for
A9
error code.
Refer to troubleshooting for
U4
error code.
Refer to troubleshooting for
U5
error code.
(R19192)
Troubleshooting