Signal Transmission Error (Between Indoor Unit And Remote Controller) - Daikin 2MXS40H2V1B Service Manual

Troubleshooting for SA Indoor Unit
6.7 Signal Transmission Error (between Indoor Unit and
Remote Controller)
U5
Error Code
Method of Error In case of controlling with 2 remote controllers, check the system using microcomputer if signal
transmission between indoor unit and remote controller (main and sub) is normal.
Detection
Error Decision Normal transmission does not continue for specified period.
Conditions
Supposed
Causes
Troubleshooting
175
Connection of 2 main remote controllers (when using 2 remote controllers)
Defective indoor unit PCB
Defective remote controller PCB
Transmission error caused by noise
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Using
2 remote controllers?
NO
Do all indoor
PCB microcomputer
monitors blink?
YES
Replace the remote controller.
Return to normal?
NO
Replace the indoor unit PCB.
Return to normal?
NO
Is SS1 of
YES
both remote controllers
set to "MAIN"?
NO
Does
operation return
NO
to normal when the
power is turned off
momentarily?
YES
YES
YES
SiBE121123_A
YES
Set one remote controller to
"SUB"; turn the power supply
off once and then back on.
NO
Replace the indoor unit
PCB.
There is possibility of
malfunction caused by noise.
Check the surrounding area
and turn on again.
Normal
Normal
There is possibility of
malfunction caused by noise.
Check the surrounding area
and turn on again.
Service Diagnosis
(R13276)