Toshiba RAS-18N3KV-E Service Manual page 76

(4) Indoor fan motor automatically starts to rotate by turning on power supply
<Cause>
The IC is built in the indoor fan motor. Therefore the P.C. board is also mounted to inside of the motor.
If the P .C. board is soldered imperfectly or the IC is defective, the fan motor may automatically rotate by turning
on power supply.
<Inspection procedure>
1. Turn on breaker.
2. After Fan motor operate, off A/C by remote controller.
3. Turn off breaker for a while, then turn it ON.
3.1. If fan motor not operate, it means an unit in Auto-restart operation. (see more detail in P. 50-51)
3.2. If Fan motor still operate, follow the below.
3.2.1. Remove the grille.
3.2.2. Remove the cover terminal by release one screw.
3.2.3. Check DC voltage with CN31 connector while the fan motor is rotating.
NOTE :
• Do not disconnect the connector while the fan motor is rotating.
• Use a thin test rod.
Indoor fan starts rotating when power supply is turned on.
(Check output DC voltage of fan motor on P.C. board.)
Measure voltage between 3 (GND : BLACK)
and 5 (V line : YELLOW) of motor connector (CN31)
while indoor fan motor is rotating.
DC 1.0V or more
P.C. board is defective.
Replace P.C. board.
Under DC 1.0V
Motor is defective.
Replace motor.
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75
FILE NO. SVM-12071
P.C. board
CN31
6 (Blue)
5 (Yellow)
Yellow
4 (White)
Black 3 (Black)
2
1 (Red)
DC
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