Mitsubishi Electric CITY MULTI PUMY-P112VKM6 Service Manual page 68

6606 (A6): Signal communication error with transmission proces-
Abnormal points and detection methods
• The data of unit/transmission processor were not nor-
mally transmitted.
• The address transmission from the unit processor was
not normally transmitted.
Diagnosis of failure
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.
Does it operate normally?
OCH790 _68
sor
No
Yes
Causes and checkpoints
• Accidental disturbance such as noise or lightning surge
• Hardware malfunction of transmission processor
Replace the controller.
(Defect of error source controller).
There is no abnormality on the AC unit.
It might be caused by an external noise, so
check the transmission line to remove the
factor(s).