Troubleshooting For Indoor Unit - Toshiba RAS-18UFHP-E4 Service Manual

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?
Parts (R21,
R22, SG01,
Is fuse (F01)
YES
C15, C01,
of indoor
DB01, C02,
control board
and T01) are
blown?
NO
Is voltage
(DC 12V or 5V)
YES
indicated on
rear of indoor
control board
normal?
NO
Is DC
310 - 340V <Primary check>
NO
supplied to or this problem is
primary side one step short of
of transfer power P.C. board
switch?
YES
Are AC 14V,
and
AC 7V
NO
supplied to
secondary
side of
transfer
switch?
YES
Turn off power
supply once, and
5 second later,
turn it on again.
Is OPERATION
lamp blinking?
Is it possible to
turn on power
YES
supply by pressing
[ ]
button on
remote control?
NO
Does
transmission mark
on remote control
NO
flash normally, and
is its signal
transmitted
properly?
YES
Check selector
switch of remocon
NO
A or B is correct
same as
remote controller
YES
defective.
Refer to
block.
Are AC 14V
and AC 7V
Turn off breaker
supplied to
once and turn it
secondary
on again after
side of
removing motor.
transfer
switch?
Remote control is
defective.
Does the
fan motor
NO
connector between
1and 3
short-circuit?
YES
Microcomputer is
defective.
SW transformer
NO
(T01) or Tr (Q01)
for power supply
is defective.
YES
– 66 –
FILE NO. SVM-05015
Operation
Check item
Conceivable principle
cause
Measure
Item by symptoms
Unit operates
normally.
Refer to 9-9
Troubleshooting for
Remote Control.
Select switch to
remocon A,B for
correct same as
remote controller
Replace main P.C.
board.
Replace motor.