Mitsubishi Electric MSZ-EF22VEW Service Manual page 28

MXZ Type
Turn OFF the power supply.
Check once more if the indoor/outdoor connecting wire is not miswiring.
B
Remove the indoor/outdoor connecting wire from outdoor terminal block S3.
Short-circuit outdoor terminal block S2 and S3. 1
Is the bus-bar voltage of the inverter P.C. board or the outdoor electronic control P.C. board normal?
(Refer to "TEST POINT DIAGRAM AND VOLTAGE" of the outdoor unit.)
Does the LED on the inverter P.C. board or the outdoor electronic control P.C.
board repeat "3.6-second-OFF and 0.8-second-ON quick blinking"? 3
Turn OFF the power supply.
Remove the short-circuit between outdoor terminal block S2 and S3.
Connect the indoor/outdoor connecting wire to outdoor terminal block S3.
Turn ON the power supply.
Is there rated voltage between indoor terminal block S1 and S2?
<Confi rmation of power voltage>
Is there amplitude of 10 to 20 VDC between indoor terminal block S2
and S3? <Confi rmation of serial signal>
A
• Turn OFF inverter-controlled lighting
equipment.
• Turn OFF the power supply and then
turn ON again.
• Press EMERGENCY OPERATION
switch.
• Reinstall
either the unit
or the light
away from
Is serial signal each other.
• Attach a fi lter
error indicated 6
No
on remote
minutes later?
control receiv-
Yes
ing section
of the indoor
unit.
B
Turn OFF the power supply.
Is there rated voltage in the power supply?
Yes
Turn ON the power supply.
Is there rated voltage between outdoor terminal block S1 and S2?
Yes
Press EMERGENCY OPERATION switch once.
Does the left lamp of OPERATION INDICATOR
lamp light up? <Confi rmation of the power to
the indoor unit>
Yes
Is serial signal error indicated 6 minutes later?
Yes
A
Turn ON the power supply.
Yes
Yes
Yes
Yes
Is there 2 VDC or less between CN102 (+)
and JPG (GND)(-) on the indoor electronic
control P.C. board?
Yes
Is there 2 VDC or less between
CN102 (+) and JPG (GND)(-) on
the indoor electronic control P.C.
board?
Replace the indoor power
P.C. board.
Check the power supply.
No
No
Is there any miswiring,
poor contact, or wire
disconnection of the
No
indoor/outdoor connect-
ing wire?
1. Miswiring may damage indoor electronic control P.C.
board during the operation.
Be sure to confi rm the wiring is correct before the opera-
tion starts.
3. Be sure to check this within 3 minutes after turning ON.
After 3 minutes, LED blinks 6 times. Even when the
inverter P.C. board or the outdoor electronic control P.C.
board is normal, LED blinks 6 times after 3 minutes.
(Except for outdoor unit of multi system type)
Replace the inverter P.C. board or the outdoor
electronic control P.C. board. 2
No
(Lighted
2. Be careful of the residual voltage of smoothing
or not
lighted)
Check the wiring.
If there are any error of the indoor/outdoor connecting wire:
such as the damage of the wire, intermediate connection,
No
and/or poor contact to the terminal block, replace the indoor/
outdoor connecting wire.
No
No
Is there 2 VDC or less between
CN102 (+) and JPG (GND)(-) on
the indoor electronic control P.C.
board?
No Yes
Replace the indoor elec-
tronic control P.C. board.
28
No
Check the wiring.
Correct them.
Yes
No
Check of power supply.
No
capacitor.
No
Yes