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SiME281906E
Troubleshooting by Error Code
Part 6 Service Diagnosis
184
Reference
5.38 Transmission Error between Indoor Unit and Remote
Controller
Applicable
Models
All indoor unit models
Error code
U5
Method of Error
Detection
Microcomputer checks if transmission between indoor unit and remote controller is normal.
Error Decision
Conditions
The transmission between the indoor unit and the remote controller is not normal over a certain
amount of time.
Supposed
Causes
Defective remote controller
Defective indoor unit PCB
External factor (Noise, etc.)
Connection of 2 main remote controllers (when using 2 remote controllers).
Troubleshooting
Refer to Main/Sub setting on page 34.
Set one of the remote controllers to
Sub, turn OFF the power supply
temporarily, then restart operation.
Main/Sub
setting of both remote
controllers is set to
Main.
Control by 2 remote
controllers
YES
NO
YES
NO
Replace the indoor unit PCB.
Resets
normally when power
supply is turned OFF
temporarily.
All indoor unit
PCB microcomputer normal
monitors blinking
The error could be produced by noise.
Check the surrounding area and
restart operation. (Ex.: Heavy-duty
wireless equipment, etc.)
YES
Caution
Be sure to turn off the power switch before connecting or disconnecting connectors, or parts may be damaged.
NO
NO
NO
YES
Is operation normal?
Normal.
YES
NO
Is operation normal?
Normal.
YES
The error could be produced by noise.
Check the surrounding area and
restart operation.
Replace the remote controller and
restart operation.
Replace the indoor unit PCB and
restart operation.