Sinclair SDV 6 Service Manual page 91

8.1.22 C73 - Abnormal communication between the linked humidifying IDU and master IDU
Error display
Error impact
Error trigger
Error recovery
Possible cause
Troubleshooting
88
Digital display
Master IDU: operates normally. Humidifying IDUs: stop. Other IDUs of the same system: operate
normally.
ODU of the same system: operate normally.
If the main control board of the master IDU has lost communication with the main control board of
the humidifying IDU for 2 min
Automatic recovery
 The main control board of the humidifying IDU is damaged.
 The master IDU's main control board is damaged.
 Communication cables are loose or the communication port is faulty.
Communication cables have short-circuited or been cut off.

C73
Note:
1. The error code can be queried after the humidifying IDU is connected to the wired controller or
the display box.
Display position (master IDU)
Panel or display box
Spot check interface
query
Cause 1: The co mmuni cation
cable between th e main control
boa rd o f th e h umidifying IDU and
the ma in control boa rd o f master
IDU is disconnected or sho rt
circuite d
Cause 2: The co mmuni cation
cable between th e main control
boa rd o f th e h umidifying IDU and
the ma in control boa rd o f th e
master IDU has b eco me loo se or
is conn ected to a wrong po rt
Cause 3: The ma in con trol boa rd
of the master IDU is damag ed
Cause 4: The ma in con trol boa rd
of the humidifying IDU is
damag ed
Wired controller
Error code is not
displayed
Replace th e
commu nicatio n cable an d
prop erly conn ect the
cable
Pro perly conn ect the
cables and ensure th ey
are conne cted to the right
ports
Replace th e main control
boa rd o f th e master IDU
Replace th e main control
boa rd o f th e h umidifying
IDU