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11. HOW TO DIAGNOSE THE TROUBLE
The pulse motor circuits are mounted to both indoor and outdoor units. Therefore, diagnose troubles according
to the trouble diagnosis procedure as described below. (Refer to the check points in servicing written on the
wiring diagrams attached to the indoor/outdoor units.)
K
Precautions when handling the new inverter (3DV Inverter)
CAUTION: HIGH VOLTAGEN
The high voltage circuit is incorporated.
Be careful to do the check service, as the electric shock may be caused in case of touching parts on the
P.C. board by hand.
The new inverter (3DV inverter) will be incorporated starting with this unit.
(3DV: 3-shunt Discrete Vector control)
K
The control circuitry has an uninsulated construction.
No.
1
2
3
4
5
First Confirmation
Primary Judgment
Judgment by Flashing LED of Indoor Unit
Self-Diagnosis by Remote Controller
Judgment of Trouble by Every Symptom
69
70
70
71
74
No.
6
7
8
Troubleshooting Procedure
How to Diagnose Trouble in Outdoor Unit
How to Check Simply the Main Parts
How to Simply Judge Whether Outdoor
Fan Motor is Good or Bad
82
83
84
IGBT × 6
FET × 6
MCU
Compressor
Fan motor
Shared potential
Driver
Driver
Amplifier
Amplifier
Fig. 11-1
FILE NO. SVM-07013
Page
9
Check Code 1C (Miswiring in
89
indoor/outdoor units) and 1E
10
P.C. Board Layout
93
Table 11-1
Page
Troubleshooting Procedure