FILE NO. SVM-02009
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9-6. Troubleshooting for Indoor Unit
9-6-1. Power can not be turned on. (The unit does not operate at all.)
<Primary check>
(1) Is the supply voltage normal?
(2) Is the connection to the AC output OK?
(3) Are the connection of the primary side and the secondary side of
the power transformer inserted into the P.C. board?
(4) Is the fuse (F01) blown?
Operation
Measure
Item by symptoms
Check item
Conceivable principle
cause
Turn off power
supply once, and
5 second later,
turn it on again.
Is OPERATION
lamp blinking?
Is it possible to
turn on power
supply by pressing
[START/STOP]
button on
remote control?
Does
transmission mark
on remote control
flash normally, and
is its signal
transmitted
properly?
Check selector
switch of remocon
A or B is correct
same as
remote controller
Select switch to
remocon A,B for
correct same as
remote controller
Remote control is
defective.
Refer to 9-9
Troubleshooting for
Remote Control.
Unit operates
normally.
Is fuse (F01)
of indoor
control board
blown?
Parts (R21,
R22, SG01,
C15, C01,
DB01, C02,
and T01) are
defective.
Does the
fan motor
connector between
1
and
3
short-circuit?
Is voltage
(DC 12V or 5V)
indicated on
rear of indoor
control board
normal?
Microcomputer is
defective.
Replace main P.C.
board.
Is DC
310 - 340V
supplied to
primary side
of transfer
switch?
Refer to
<Primary check>
or this problem is
one step short of
power P.C. board
block.
Are DC 15V,
DC 12V and
DC 7V
supplied to
secondary
side of
transfer
switch?
Turn off breaker
once and turn it
on again after
removing motor.
Are DC 12V
and DC 7V
supplied to
secondary
side of
transfer
switch?
SW transformer
(T01) or Tr (Q01)
for power supply
is defective.
Replace motor.
NO
NO
NO
NO
NO
NO
NO
NO
NO
YES
YES
YES
YES
YES
YES
YES
YES
YES
