Mitsubishi Electric MSZ-HJ50VA Service Manual download pdf (Page 15)

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) 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.

Insert the minus pole of the

batteries first. Check if the polarity

of the batteries is correct.

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.

Press RESET button with a thin instrument, and

then use the remote controller.

Remove the back lid and insert batteries.

Then reattach the back lid.

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 housing of the connector. DO NOT pull the lead wires.

MSZ-HJ25VA MSZ-HJ35VA MSZ-HJ50VA

TROUBLESHOOTING

Lead wiring

Housing point

OBH647A

1 2 ... 10 11 12 13 14 15 16 17 18 19 20 ... 31 32

No comments

Mitsubishi Electric MSZ-HJ50VA Service Manual Page 15