40
TROUBLESHOOTING
11
11-1. Cautions on troubleshooting
1. Before troubleshooting, check the following:
1) Check the power supply voltage.
2) Check the indoor/outdoor connecting wire for mis-wiring.
2. Take care the following during servicing.
1) Before servicing the air conditioner, be sure to first turn off the remote controller to stop the unit, and then after con-
firming the horizontal vane is closed, turn off the breaker and / or disconnect the power plug.
2) Be sure to unplug the power cord before removing the front panel, the cabinet, the top panel, and the P.C. boards.
3) When removing the P.C. board, hold the edge of the board with care NOT to apply stress on the components.
4) When connecting or disconnecting the connectors, hold the housing of the connector, DO NOT pull the lead wires.
Housing point
Insert the negative pole
of the batteries first.
Check if the polarity of
the battereis is correct.
RESET button
Lead wiring
3. Caution for the outdoor unit repair service
1) Do not load on the P.C.board cover.
2) Since every P.C.board circuit links directly with
power supply 220~240V AC, do not short the
P.C.board and metal section on servicing. Also
if touch the parts on the P.C.board, it may cause
an electric shock.
3) When closing the P.C.board cover, prevent a
foreign matter or dust from coming inside the
P.C.board.
Cover
Relay P.C. board
Electronic control P.C. board
MSZ-A09RV -
MSZ-A12RV -
E1
E1
3. Troubleshooting procedure
1) First, check if the POWER MONITOR lamp on the indoor unit is flashing on and off to indicate an abnormality. To
make sure, check how many times the abnormality indication is flashing on and off before starting service work.
2) Before servicing check that the connector and terminal are connected properly.
3) If the P.C. board is supposed to be defective, check the copper foil pattern for disconnection and the components for
bursting and discoloration.
4) When troubleshooting, refer to the flow chart on page 41 and the check table on page 42 and 43.
4. How to replace batteries
Weak batteries may cause the remote controller malfunction.
In this case, the remote controller can not be repaired only by the battery replacement. To operate the remote controller
normally, replace the batteries in the following order.
This remote controller has the RESET button. After refilling new batteries, press the RESET button with tip end of ball
point pen or the like, and then use the remote controller.
1
Remove the back lid and replace batteries.
Then re-attach the back lid.
2
Press the RESET button.
MUZ-A09RV -
MUZ-A12RV -
E1
E1
OB230-2.qxp 02.5.28 7:37 PM Page 40
