MXZ-SM42NAMHZ Service Manual

99
OCH789
Check code
6608
(A8)
Abnormal points and detection methods Causes and checkpoints
If receiving no response command while already received ACK.
The sending side searches the error in 30 seconds interval for 6 times
continuously.
Continuous failure of transmission due to noise etc
Decline of transmission voltage/signal caused by
tolerance over on transmission line
·At the furthest end: 656 ft [200 m]
·On remote controller line: 39 ft [12 m]
Decline of transmission voltage/signal due to
unmatched transmission line types
·Types for shield line: CVVS, CPEVS, or MVVS
·Line diameter: AWG 16 [1.25
E
]
Accidental malfunction of error source controller
●Diagnosis of defects
Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards.
Diagnosis Remedy
No response frame error
●Diagnosis of defects
Make sure to turn the power OFF before connecting/disconnecting any connectors, or replacing boards.
*For the tolerance, refer to the
Installation Manual.
Yes
Yes
Yes
Yes
No
No
No
No
Does it operate normally?
The transmission line is connected
properly.
It is not exceeding the tolerance.
Is correct kind of transmission line
used?
Replace the controller board
(Defect of the controller which the
displayed address/attribute belong to).
Connect the transmission line properly.
Correct it within the tolerance.
Replace it with the correct kind of
transmission line.
There is no abnormality on the AC unit.
Check the transmission line for
transmission wave and noise.
Turn the power OFF of indoor/outdoor unit, Fresh
Master, Lossnay and remote controller simultaneously
for 2 minutes or more, then turn the power back ON.
Check the transmission line for a
disconnection and looseness
(on the terminal board and connector).
Check the transmission line whether it
exceeds the tolerance(*) or not.
Check whether the correct kind of
transmission line is used or not.