Mitsubishi Electric SUZ-KA09NA2 Service Manual page 23

J Check of power supply
Disconnect the connector between
compressor and intelligent power
module.
Turn ON power supply and press
the TEST button twice on the indoor
unit or remote controller.
Does the POWER lamp on remote
controller light up?
Yes
Is there bus-bar voltage 260-370 VDC
between DB61 (+) and DB61 (–) on
the inverter P.C. board? (Refer to "10-
6.TEST POINT DIAGRAM AND VOLTAGE.")
No
Check the electric parts in main circuit.
K Check of LEV (Expansion valve)
Start
Turn on power supply to the outdoor unit after checking
LEV coil is fixed to the LEV body securely.
Is "click - click" sound heard?
Or, do you feel vibration of the LEV coil with a hand?
Disconnect the connector CN724 is there
normal resistance to LEV coil? (Refer to 10-4.
TROUBLE CRITERION OF MAIN PARTS)
Replace the LEV coil.
OCH699A
Rectify indoor/outdoor
connecting wire.
Is there voltage 208/230 VAC
between the indoor terminal
No
block S1 and S2?
Does LED on the inverter P.C. board
light up or blink? (Refer to "10-6.TEST
Yes
POINT DIAGRAM AND VOLTAGE.")
If light up, OK.
If blink, refer to "10-3. HOW TO
PROCEED "SELF-DIAGNOSIS"".
No
Yes
No
Yes
Yes
Normal
Yes
Replace the inverter P.C. board.
23
Replace the indoor
electronic control P.C.
No
board.
Replace the inverter
No
P.C. board.
260-370 VDC
DB61
Inverter P.C. board
(Solder side)