Mitsubishi Electronics MSY-A17NA, MSY-A24NA Check of indoor fan motor, Troubleshooting flow

8-6. Troubleshooting flow

When OPERATION INDICATOR lamp flashes 3-time. Indoor fan does not operate.

A Check of indoor fan motor

The indoor fan motor error has occurred, and the indoor fan doesn't operate.

Turn OFF the power supply.

Is there any foreign matter that interferes the rotation of the line flow fan?

Yes

Remove the foreign matter and adjust the line flow fan.

No

Pay careful attention to the high voltage on the fan motor connector CN211.

Turn ON the power supply, wait 5 seconds or more, and then press EMERGENCY OPERATION switch.

Measure the supply voltage as follows within 12 seconds after EMERGENCY OPERATION switch is pressed.

If more than 12 seconds passes by, turn OFF the power supply and turn ON it again, then measure the voltage. w

1.Measure the voltage between CN211 1(+) and 3(-). 2.Measure the voltage between CN211 5(+) and 3(-).

wIf more than 12 seconds or more passes after EMERGENCY OPERATION switch is pressed, the voltage mentioned above 2 goes 0V DC although the indoor electric control P.C. board is normal.

Is there 294/325V DC between
CN211 1 (+) and 3 (-), and does
the voltage between CN211 5(+)		Yes
and 3(-) rise to the range of 3 to 6V			Replace the indoor fan motor.
DC within 12 seconds after
EMERGENCY OPERATION switch
is pressed?
	No

Indoor electronic control P.C. board

CN211

Replace the indoor electronic control P.C. board.

The indoor fan motor error has occurred, and the indoor fan repeats "12-second ON and 30-second OFF" 3times, and then stops.

Measure the voltage between CN211 6(+) and 3(-) while the fan

motor is rotating.

	No
Is it unchanged holding	(Changed)
	Replace the indoor electronic control P.C. board.
0V DC or 15V DC?

Yes (Unchanged)

Replace the indoor fan motor.

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