Mitsubishi Electric MR. SLIM PCA Series Service Manual page 34

9-4. TROUBLESHOOTING OF PROBLEMS
Phenomena
(1) LED2 on indoor controller board
is off.
OCH659A
Note: Refer to the outdoor unit's service manual for the detail of remote controller.
Cause
• When LED1 on indoor controller board is also off.
Power supply of rated voltage is not supplied to out-
door unit.
Defective outdoor controller circuit board
Power supply of 220–240 V is not supplied to indoor
unit.
Defective indoor controller board
(For the separate indoor/outdoor unit power sup-
ply system)
Power supply of 220–240 V AC is not supplied to
indoor unit.
The connectors of the optional replacement kit are
not used.
Defective indoor controller board
• When LED1 on indoor controller board is lit.
Mis-setting of refrigerant address for outdoor unit
(There is no unit corresponding to refrigerant address
"0".)
Check the voltage of outdoor power
supply terminal block (L, N) or (L
• When 220–240 V AC is not detected,
check the power wiring to outdoor unit
and the breaker.
• When 220–240 V AC is detected, check
Check the voltage between outdoor
terminal block S1 and S2.
• When 220–240 V AC is not detected,
—check the fuse on outdoor controller
circuit board.
—check the wiring connection.
• When 220–240 V AC is detected, check
Check the voltage between indoor
terminal block S1 and S2.
• When 220–240 V AC is not detected,
check indoor/outdoor unit connecting
wire for miswiring.
• When 220–240 V AC is detected, check
Check the fuse on indoor controller board.
Check the wiring connection.
If no problem is found, indoor controller
board is defective.
Check the voltage of indoor power supply
terminal block (L,N).
• When 220–240 V AC is not detected,
check the power supply wiring.
• When 220–240 V AC is detected, check
Check that there is no problem in the
method of connecting the connectors.
• When there are problems in the method
of connecting the connectors, connect
the connector correctly referring to
installation manual of an optional kit.
• When there is no problem in the method
of connecting the connectors, check
(below).
Check the fuse on indoor controller board.
Check the wiring connection.
If no problem is found, indoor controller
board is defective.
Check again the setting of refrigerant
address for outdoor unit.
Set the refrigerant address to "0".
(For grouping control system under which
2 or more outdoor units are connected,
set one of the units to "0".)
Set refrigerant address using SW1 (3-6)
on outdoor controller circuit board.
34
Countermeasure
, N).
3
(below).
(below).
(below).
(below).