Mitsubishi Electric Mr. Slim MUZ-GE15NA-1, Service Manual

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10
TROUBLESHOOTING
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, then after con-
firming 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 electronic
control P.C. board.
3) When removing the electrical parts, be careful of the residual voltage of smoothing capacitor.
4) When removing the electronic control P.C. board, hold the edge of the board with care NOT to apply stress on the
components.
5) When connecting or disconnecting the connectors, hold the housing of the connector. DO NOT pull the lead wires.
3. Troubleshooting procedure
1) Check if the OPERATION INDICATOR lamp on the indoor unit is flashing ON and OFF to indicate an abnormality.
To make sure, check how many times the OPERATION INDICATOR lamp is flashing ON and OFF before starting
service 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) Refer to 10-2. and 10-3.
<Correct>
Lead wiring Housing point
<Incorrect>
MUZ-GE09NA MUZ-GE12NA MUZ-GE15NA MUZ-GE18NA MUZ-GE24NA
MUZ-GE09NA2 MUZ-GE12NA2 MUZ-GE15NA2
MUZ-GE09NAH MUZ-GE12NAH MUZ-GE15NAH MUZ-GE18NAH
MUZ-GE09NAH2 MUZ-GE12NAH2 MUZ-GE15NAH2
MUY-GE09NA MUY-GE12NA MUY-GE15NA MUY-GE18NA
MUY-GE24NA
MUY-GE09NA2 MUY-GE12NA2 MUY-GE15NA2
OBH549F