Mitsubishi Electric MSZ-A09RV-E1 Service Manual page 47

(How to check inverter/compressor)
Start
Disconnect the connector between compressor and IPM.
Check voltage
between terminals.
Are voltages
balanced?
Yes
Check
compressor.
A
Check of open phase
Be sure to use the analog voltmeter for measurement
With the connector between compressor and transistor module
disconnected, activate the inverter and measure the balance of
voltage between terminals.
Output voltage : 120V
<< Operation method>>
Start heating opration by pressing the Emergency operation switch
on the indoor unit. (test-run mode)
<<Measurement point>>
at 3 points
BLK-WHT
BLK-RED
WHT-RED
NOTE Measure AC voltage, at 3 points more than one minute ofter
the outdoor fan motor starts running.
B
Check of IPM
Disconnect the connector between compressor and IPM, and
measure resistance between terminals on the IPM.
<<Measurement point>>
at 6 points
BLK-WHT, WHT-BLK
BLK-RED, RED-BLK
WHT-RED, RED-WHT
at 6 points
<<Judgment>>
Infinite ["]···········normal
0~dozens of ······abnormal (short)
See A 'Check of open phase.'
No
Check resistance of IPM.
See C 'Check of compressor.'
w Measure resistance between
the lead wires at 3 points
See B 'Check of transistor module.'
Is resistance
infinite?
No
(0~several
<Outdoor electronic control P.C. board>
IPM
PFC
9 flashes
Note 1. Output voltage changes depending power supply
voltage. (Max. i10%)
2. Measure by analogue tester.
3. During the measurement, LED in the outdoor electronic
control P.C. board flashes 9 times.
ohmmeter indication
"
X1
"
X1
47
Yes
Outdoor electronic control
P.C. board is defective
Replace outdoor
"
)
electronic control P.C.
board and IPM.
IPM is defective.
LED
flash
2.5 seconds OFF
normal
(infinite)
abnormal
(0~dozens of ")