Check of indoor p.c. board and indoor fan motor – MITSUBISHI ELECTRIC MSZ-FD25VAS User Manual

Page 30

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The unit does not operate with the remote controller.
Also, POWER lamp does not light up by pressing EMERGENCY OPERATION switch.

Check of indoor P.C. board and indoor fan motor

C

Yes

No

w

1. The fan motor connector's

1

lead wire is red, whereas

3

is black.

w

2. Connect "+" of the tester to fan motor connector's

1

lead

wire, and "-" to

3

lead wire, otherwise the resistance cannot be

measured properly.

Yes

No

Does the unit operate with the remote controller?
Does POWER lamp light up by pressing EMERGENCY
OPERATION switch?

Turn OFF the power supply.
Remove indoor fan motor connector CN211, vane motor
connector CN151 and the i-see Sensor motor connector
CN110 from the indoor electronic control P.C. board and
turn ON the power supply.

Measure the resistance of the horizontal vane
motor coil and the vertical vane motor coil.
Refer to 10-5.

Measure the resistance between CN211

3

and

4

of the indoor fan motor connector.

Short/open circuit:
Replace the indoor fan motor.

Short/open circuit:
Replace the horizontal vane motor, the
vertical vane motor and the indoor
electronic control P.C. board.

Turn OFF the power supply.
Check both “parts side” and “pattern
side” of the indoor electronic control P.C.
board visually.

Replace the varistor(NR11) and fuse(F11).

Are the varistor(NR11) burnt
and the fuse(F11) blown?

Be sure to check both the fuse
and the varistor in any case.

No

Yes

No

Is the fuse(F11) blown only?

Yes

No

Is the resistance 1 M

"

or more?

Measure the resistance between

1

(+) and

3

(-) of the indoor fan

motor connector.

w

1,

w

2

Replace the fuse (F11).

Replace the fuse (F11) and the indoor fan motor.

Is the resistance
approx. 4

"

?

Measure the resistance of cement
resistor(R111) on the indoor electronic
control P.C. board.

Replace the indoor electronic control P.C. board.

Replace the indoor electronic control P.C. board
and the indoor fan motor.

Yes

Measure the resistance of the i-see Sensor
motor coil.
Refer to 10-5.

Short/open circuit:
Replace the i-see Sensor motor
and the indoor electronic control P.C.
board.

OBH488-1.qxp 07.8.9 11:47 AM Page 30

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