Troubleshooting - Mitsubishi Electric MSZ-EF18VE2B-E1 Service Manual

10

TROUBLESHOOTING

MSZ-EF18VEW MSZ-EF22VEW MSZ-EF25VEW MSZ-EF35VEW MSZ-EF42VEW MSZ-EF50VEW
MSZ-EF18VEB MSZ-EF22VEB MSZ-EF25VEB MSZ-EF35VEB MSZ-EF42VEB MSZ-EF50VEB
MSZ-EF18VES MSZ-EF22VES MSZ-EF25VES MSZ-EF35VES MSZ-EF42VES MSZ-EF50VES
MSZ-EF18VE2W MSZ-EF22VE2W MSZ-EF25VE2W MSZ-EF35VE2W MSZ-EF42VE2W MSZ-EF50VE2W
MSZ-EF18VE2B MSZ-EF22VE2B MSZ-EF25VE2B MSZ-EF35VE2B MSZ-EF42VE2B MSZ-EF50VE2B
MSZ-EF18VE2S MSZ-EF22VE2S MSZ-EF25VE2S MSZ-EF35VE2S MSZ-EF42VE2S MSZ-EF50VE2S
MSZ-EF18VE3W MSZ-EF22VE3W MSZ-EF25VE3W MSZ-EF35VE3W MSZ-EF42VE3W MSZ-EF50VE3W
MSZ-EF18VE3B MSZ-EF22VE3B MSZ-EF25VE3B MSZ-EF35VE3B MSZ-EF42VE3B MSZ-EF50VE3B
MSZ-EF18VE3S MSZ-EF22VE3S MSZ-EF25VE3S MSZ-EF35VE3S MSZ-EF42VE3S MSZ-EF50VE3S
10-1. CAUTIONS ON TROUBLESHOOTING
1. Before troubleshooting, check the following
1) Check the power supply voltage.
2) Check the indoor/outdoor connecting wire for miswiring.
2. Take care of the following during servicing
1) Before servicing the air conditioner, be sure to turn OFF the main unit first with the remote controller, and then after
confirming the horizontal vane is closed, turn OFF the breaker and/or disconnect the power plug.
2) Be sure to turn OFF the power supply before removing the front panel, the cabinet, the top panel, and the P.C. board.
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 connector housing. DO NOT pull the lead wires.
3. Troubleshooting procedure
1) Check if the OPERATION INDICATOR lamp on the indoor unit is blinking ON and OFF to indicate an abnormality.
To make sure, check how many times the OPERATION INDICATOR lamp is blinking ON and OFF before starting ser-
vice work.
2) Before servicing, check that the connector and terminal are connected properly.
3) When the electronic control P.C. board seems to be defective, check the copper foil pattern for disconnection and the
components for bursting and discoloration.
4) When troubleshooting, Refer to 10-2, 10-3 and 10-4.
4. How to replace batteries
Weak batteries may cause the remote controller malfunction.
In this case, replace the batteries to operate the remote controller normally.
Remove the front lid and insert batteries.
Then reattach the front lid.
NOTE: 1. If RESET button is not pressed, the remote controller may not operate correctly.
2. This remote controller has a circuit to automatically reset the microcomputer when batteries are replaced.
This function is equipped to prevent the microcomputer from malfunctioning due to the voltage drop caused by the
battery replacement.
3. Do not use the leaking batteries.
OBH589G
<Incorrect>
Lead wiring
Insert the negative pole of the
batteries first. Check if the polarity
of the batteries is correct.
<Correct>
Connector housing
Press RESET button with a thin instrument, and
then use the remote controller.
29
RESET button