Midea V8 VRF Series Service Manual page 73

V8 VRF Indoor Units
6.1.25 C76 - Abnormal communication between the main wired controller and secondary wired controller
Note: The error code C51 can be triggered either at the IDU side or at the wired controller side.
Error display
The faulty IDU and other IDUs of the same system: operate normally. The wired controller does not work.
Error impact
ODU of the same system: operate normally.
Error trigger If the secondary wired controller has not received any reply from the main wired controller for 1 min
Error recovery
Automatic recovery
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Possible cause
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Troubleshooting
72
Digital display
The secondary wired controller is damaged.
Communication cables are loose or the communication port is faulty.
Communication cables have short-circuited or been cut off.
C76
Display position (secondary wired controller)
The error code "C76" is displayed only on the secondary wired
controller
Cause 1: The co mmuni cation
cable between th e seconda ry
wired controller and the ma in
wired controller has become
disconnected or sho rt ci rcu ited
Cause 2: The co mmuni cation
cable between th e seconda ry
wired controller and the ma in
wired controller has become
loose or is conne cted to a wrong
port
Cause 3: The se con dary wired
controller is d ama ged
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 seconda ry
wired controller