Dc Fan Motor (Fan Motor/Indoor Control Board) - Mitsubishi Electric CITY MULTI PEFY-P20VMAL Technical & Service Manual

[ VII Troubleshooting ]

2. DC fan motor (fan motor/indoor control board)

1. CAUTION
A high voltage is applied to the connector for connection to the fan motor (CNMF).
Do not unplug the connector CNMF with the unit energized to avoid damage to the indoor control board and fan motor.
2. Troubleshooting
Symptom: Indoor unit fan does not run.
Check fan motor connector contact
(CNMF).
Is the fan motor connector
(CNMF) fully inserted?
Yes
Check the power supply.
Measure the voltage at the indoor control board.
310 - 340VDC (same with the voltage between fan connector 1 (+) and 4(-))
Power supply voltage
15VDC (same with the voltage between fan connector 5 (+) and 4(-))
1 - 6.5VDC (same with the voltage between fan connector 6 (+) and 4(-))
[Values for Vsp are the values that are measured with the fan motor in operation.
Vsp is 0V when the fan motor is stopped.]
Is the voltage within the
normal range?
Yes
Check the fan motor position thermistor signal.
Get the motor to make a full rotation or more, and measure the voltage at the test point
V .
FG
(same with the voltage between fan connector 7 (+) and 4(-))
Are 0VDC and 15VDC
displayed alternately?
Yes
Replace the indoor control board.
HWE0812B
No
Fix the connection.
V
DC
No
Replace the indoor control board.
No
Replace the motor.
- 18 -
GB