Signal Transmission Error (Between Indoor Unit And Remote Controller) - Daikin 4MXL-T Series Service Manual

Troubleshooting for SA Indoor Unit
6.10 Signal Transmission Error (Between Indoor Unit and
Remote Controller)
U5
Error Code
Method of Error In case of controlling 1 indoor unit with 2 remote controllers, check the system using microcomputer
Detection if signal transmission between indoor unit and remote controller (main and sub) is normal.
Error Decision Normal transmission does not continue for specified period.
Conditions
Supposed  Connection of 2 main remote controllers (when using 2 remote controllers)
Causes  Defective indoor unit PCB
 Defective remote controller
 Transmission error caused by noise
Troubleshooting
Note
For the way to change MAIN/SUB setting of remote controllers, refer to pages 267 and 268.
192
Be sure to turn off the power switch before connecting or disconnecting
Caution connectors, or parts may be damaged.
Using
YES
2 remote controllers
for 1 indoor unit?
NO
Do the service
monitors of all the indoor
units blink?
YES
Replace the remote controller.
Return to normal?
NO
Replace the indoor unit PCB.
Return to normal?
YES
Are both
remote controllers set to
MAIN?
NO
Does
operation return to
NO
normal when the power is
turned off
momentarily?
YES
YES
NO
SiUS121827E
YES
Set 1 remote controller to
SUB; turn the power supply
off once and then back on.
When using both wired and
wireless remote controllers for
1 indoor unit, make sure to set
the wireless remote controller
to SUB.
NO
Replace the indoor unit
PCB (control PCB).
There is possibility of
malfunction caused by noise.
Check the surrounding area
and turn on again.
Normal
There is possibility of
malfunction caused by noise.
Check the surrounding area
and turn on again.
Normal
Part 6 Service Diagnosis
(R24590)