Sinclair SDV 6 Service Manual page 86

Troubleshooting
Cause 1: The communication
cable material does not meet
the anti-interference
requirements.
Cause 2: Whether the
communication cable has a
junction or the metal oxidation
of the wire head causes the
connection to fail.
Cause 3: There is strong
electrical and electromagnetic
interference near the
communication cable.
Cause 4: Whether the
communication cable is
disconnected or short-
circuited.
C51
Cause 5: The communication
cable is loose or the
communication port is
connected incorrectly.
Cause 6: The communication
cable connection port of the
wired controller is damaged or
the control board is damaged.
Cause 7: The main control
board of the indoor unit is
damaged.
Replace the
communication cable that
meets the anti-interference
requirements.
Reconnect the signal line
according to the wiring
requirements.
The communication cable
needs to be shielded with
a metal pipe or laid away
from the interference
source.
After replacing the
communication cable,
reconnect it.
Reconnect and ensure
that the communication
port is connected
correctly.
Replace the wired
controller.
Replace the main control
board of the indoor unit.
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