Mitsubishi Electric Mr. Slim PLA-A12BA4 Service Manual page 18

• On IR wireless remote controller
The continuous buzzer sounds from receiving section of indoor unit.
Blink of operation lamp
• On wired remote controller
Check code displayed in the LCD. (Refer to the previous page,
• If the unit cannot be operated properly after the test run, refer to the following table to find out the cause.
Wired remote controller
PLEASE WAIT
PLEASE WAIT Error code
Display messages do not
appear even when operation
switch is turned ON (operation
lamp does not light up).
On the IR wireless remote controller with condition above, following phenomena take place.
• No signals from the remote controller can be received.
• OPE lamp is blinking.
• The buzzer makes a short ping sound.
Note:
Operation is not possible for about 30 seconds after cancellation of function selection. (Correct operation)
For description of each LED (LED1, 2, 3) provided on the indoor controller, refer to the following table.
LED1 (power for microprocessor)
LED2 (power for wired remote controller)
LED3 (communication between indoor and
outdoor units)
Symptom
LED 1, 2 (PCB in outdoor unit)
For about 2
After LED 1, 2 are lighted, LED 2 is
turned off, then only LED 1 is
minutes after
lighted. (Correct operation)
power-on
Only LED 1 is lighted.
Subsequent to
about 2 minutes
after power-on
Only LED 1 is lighted.
Indicates whether control power is supplied. Make sure that this LED is
always lit.
Indicates whether power is supplied to the wired remote controller.
This LED lights only in the case of the indoor unit which is connected to the
outdoor unit refrigerant addresses "0".
Indicates state of communication between the indoor and outdoor units.
Make sure that this LED is always blinking.
check code.)
•For about 2 minutes following power-on,op-
eration of the remote controller is not possible
due to system start-up. (Correct operation)
•Connector for the outdoor unit's protection
device is not connected.
•Reverse or open phase wiring for the outdoor
LED 1, 2 blink.
unit's power terminal block (L1, L2, GR)
•Incorrect wiring between indoor and outdoor
units (incorrect polarity of S1, S2, S3)
LED 1 blinks twice,
•Remote controller wire short
LED 2 blinks once.
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Cause