Mitsubishi Electric MCFZ-A12WV Service Manual page 15

When OPERATION INDICATOR lamp flashes ON and OFF in every 0.5-second.
Outdoor unit does not operate.
How to check mis-wiring and serial signal error (when outdoor unit does not work)
D
MCFZ-A12WV
:
CLOCK
AMPM
12345
AMPM
•The following indication
applies regardless of shape
of the indicator.
Blinking
Operation Indicator
w4 Replace the inverter P.C.
board.
w4 Be careful to the residual voltage of smoothing capacitor.
As for outdoor units MUZ-A12YV and MUZ-A12YVH,
refer to service manual OB328 REVISED EDITION-A.
• Turn ON the power supply(Indoor unit).
• Press once EMERGENCY OPERATION switch.
After 3 minutes, mis-wiring is indicated
(0.5-second ON, 0.5-second OFF)
on OPERATION INDICATOR
lamp on indoor unit.w
Yes
Is there any mis-wiring, poor contact,
Make them sure.
or wire disconnection? w2
Turn OFF the power supply(Indoor unit).
Disconnect the indoor/ outdoor connecting wire.
Short-circuit indoor terminal block N and 3.
Turn ON the power supply(Indoor unit).
During pressing both the OPERATION SELECT button
and TOO COOL button on the remote controller at the
same time, press the RESET button.
At first, release the RESET button.
B
And release the other two buttons since all LCD in
operation display section of the remote controller is
displayed after 3 seconds.
Transmit the signal of remote controller, pressing
OPERATE/STOP (ON/OFF) button on the remote
controller.
(The above procedure allows OPERATION INDICATOR
lamp to indicate the failure-mode.)
Does the right side of OPERATION INDICATOR
lamp blink quickly?
Release the failure mode. w3
Remove the short-circuit between indoor terminal block N
and 3.
Reconnect the indoor/ outdoor connecting wire.
Turn ON the power supply(Indoor unit).
Press the EMERGENCY OPERATION switch.
Is there amplitude of 5 to 10V DC between outdoor
terminal block N and 3 after 3 minutes (for confirmation of
serial signal)?
Is there 230V AC between outdoor terminal
block 2 and N?
1. Turn OFF the power supply.
2. Disconnect the connector (CN61) between the
compressor and the power transistor module.
3. Turn ON the power supply.
4. Press the EMERGENCY OPERATION switch.
Is there voltage approximate 280V DC between
Yes
LD61A (+) and LD66A (–) on the inverter P.C.
board arter 3 minutes?
Turn OFF the power supply and then turn ON
again.
Press EMERGENCY OPERATION switch.
Yes
After 3 minutes, is there approximate 230V AC
between outdoor terminal block 2 and N?
Replace the indoor/ outdoor connecting wire.
Start
No
A
Yes
Yes
Yes
No
No
15
w Short circuit of JPG and JPS on the indoor
electronic control P.C. board enables
self-check to be displayed in 3 seconds.
w2 Mis-wiring may damage indoor electronic
control P.C. board during the operation.
Be sure to confirm the wiring is correct
before the operation starts.
Replace the indoor
No
electronic control
(light up or OFF)
P.C. board.
Replace the
No
indoor/ outdoor
connecting wire.
Replace the
No
indoor/ outdoor
connecting wire.
w3 Be sure to release the failure-mode
recall function after checking.
Procedure of release of failure-mode.
1 Press the EMERGENCY
OPERATION switch.
2 Turn OFF the power supply.
3 Press the RESET button on the
remote controller.
A
· Turn OFF inverter-controlled lighting
equipment.
· Turn OFF the power supply and then
turn ON again(Indoor unit).
· Press the EMERGENCY
OPERATION switch.
· Reinstall
Is mis-wiring
indicated when
the contactor
No
(52C) on the
indoor electronic
· Attach a filter
control P.C.
board turns ON
3 minutes later?
Yes
B
either the
unit or the
light each
other away.
on receiving
section of
the indoor
unit.