Samsung mini DVM Series Service Manual page 460

■ Communication Error between the Outdoor Unit Main and Sub MICOM or Communication
Error between the Outdoor Units
Outdoor unit display
Indoor unit display
Judgment method
Causes
Error reset (Key 3)
Check the outdoor unit having errors
(U200, U201, U202, and U203)
Is the power supply normal?
Check the cut cable of the
outdoor communication cable
Check the outdoor unit setting
option K13, K14
Replace the PCB.
Samsung Electronics
↔ U*** (***: Outdoor unit address which an error is occurred.)
Refer to the below judgment method
Communication inferiority between outdoor units
12V, 5V
Yes
Yes
Yes
No
Check the power.
No
cut cable changing
or connection
No
Change the setting.
Troubleshooting
12-49