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FILE NO. SVM-07018
– 63 –
A
B
C
Diagnosis/Process flowchart
Item
Check
Operation
Check
Summary
→
OK if 10M
Ω
or more
→
OK if 0.51
Ω →
0.57
Ω
(Check by a
digital tester.)
Contents
Check winding resistance
between phases
of compressor, and
resistance between
outdoor frames by using a
tester.
•
Is not grounded.
•
Is not short-circuited
between windings.
•
Winding is not opened.
Remove connector
CN300 of the outdoor fan
motor turn on the power
breaker, and perform the
operation. (Stops though
activation is prompted.)
Check operation within 2
minutes 20 seconds after
activation stopped.
OK
NG
NG
Check
winding of
compressor.
Replace
com-
pressor.
OK
Replace control
board assembly.
Check
compressor
winding
resistance.
Replace control
board.
Replace
compressor.
10-8. How to Check Simply the Main Parts
10-8-1. How to check the P.C. board (Indoor unit)
(1) Operating precautions
1) When removing the front panel or the P.C.
board, be sure to shut off the power supply
breaker.
2) When removing the P.C. board, hold the edge
of the P.C. board and do not apply force to the
parts.
3) When connecting or disconnecting the connec-
tors on the P.C. board, hold the whole housing.
Do not pull at the lead wire.
(2) Inspection procedures
1) When a P.C. board is judged to be defective,
check for disconnection, burning, or discolora-
tion of the copper foil pattern or this P.C. board.
2) The P.C. board consists of the following 2 parts
a. Main P.C. board part:
DC power supply circuit (5V, 12V), Indoor fan
motor control circuit, CPU and peripheral
circuits, buzzer, and Driving circuit of top/
bottom louvers.
b. Indication unit of infrared ray receiving
Infrared ray receiving circuit, LED:
To check defect of the P.C. board, follow the
procedure described below.