Mitsubishi MUZ-GE
Re: Test Outdoor Fan Motor
The unit uses a DCV 3-Phase fan motor.
1. Test Winding Resistance
- Disconnect power to the outdoor unit.
- Wait at least 30 seconds for the capacitors to discharge.
- Disconnect the leads to the fan motor (Red, White & Blk).
- Test resistance across the motor windings.
| Lead Color |
Normal Resistance |
| GE09/12 |
GE15 |
GE18/24 |
| Red - Blk |
28 - 40 ohms |
11 - 16 ohms |
| Blk - Wht |
| Wht - Red |
2. Test Motor Bearings
- Disconnect power to the outdoor unit.
- Wait at least 30 seconds for the capacitors to discharge.
- Rotate the fan blade manually.
- The motor should rotate smoothly.
- Test resistance across the motor windings.
3. Test Motor Feedback
- Disconnect power to the outdoor unit.
- Wait at least 30 seconds for the capacitors to discharge.
- Disconnect CN931 and CN932 from the Inverter P.C. Board
- Turn on power to the unit.
- On CN931, check DC voltage across the pins as you manually rotate the motor.
- Between 1(+) and 5(-)
- Between 2(+) and 5(-)
- Between 3(+) and 5(-)
- DC voltage should alternate between 0 and 5 vdc.