Toshiba RAS-M10UKCV-E Service Manual page 64

Diagnosis/Process flowchart
A B
compressor.
Check
fan motor
NG
position
detect
signal.
OK
Replace
outdoor
fan
motor.
Replace control
board assembly.
Check
NG
compressor
winding
resistance.
OK
Replace
control board.
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
connectors on the P.C. board, hold the whole
housing. Do not pull at the lead wire.
C
Check
NG
winding of
OK
Replace
Operation
com-
pressor.
Replace
compressor.
Item Contents
Check Check winding resistance
between phases of compres-
sor, 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.
Check <Output check of fan motor
position detect signal>
While connecting connector
5P (CN301) for position
detection, using a tester,
measure voltage between
U
- . Between
(2) Inspection procedures
1) When a P.C. board is judged to be defective,
check for disconnection, burning, or discol-
oration 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, 35V),
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.
– 64 –
→ → → → → OK if 10MΩ or more

→ → → → → OK if 0,51Ω → 0,57Ω


(Check by a digital tester.)
a) One or two of three
voltages should be 5V,
and others should be 0V.
(When all are 0V or 5V, it
is not accepted.)
Q
b) When rotating the fan
U T
- : 5V slowly with hands, the
voltage between pins
should move from 0V to
5V.
(Check it with an analog
tester.)
Summary