Troubleshooting - Mitsubishi Electric MCFH-13NV-E4 Service Manual

10-5. RELEASE OF AUTO RESTART FUNCTION
Solder JHA (refer to page 52) with a jumper line on the indoor electronic control P.C. board.
Remove the auto restart assy from "Connector CN104".
11

TROUBLESHOOTING

MCFH-13NV -
E4
MCFH-18NV -
E3
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 service.
(1) Before servicing the air conditioner, be sure to first turn off the remote controller to stop the main unit, and then after
confirming the horizontal vane has completely closed, turn off the breaker.
(2) Be sure to unplug the power cord before removing the air inlet grille, the front panel, the cabinet, the top panel and
the electronic control P.C. boards.
(3) When removing the electronic control 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.
3. Troubleshooting procedure
(1) First, 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 abnormality indication is flashing on and off before starting service work.
(2) If the electronic control P.C. board is supposed to be defective, check the copper foil pattern for disconnection and
the components for bursting and discoloration.
(3) When troubleshooting, refer to the flow chart and the check table on page 43 and 44.
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.
1 Remove the front lid and insert batteries.
Then re-attach the front lid.
NOTE : If the RESET button is not pressed, the remote controller may not operate correctly.
MCFH-24NV -
E3
Insert the negative pole
of the batteries first.
Check if the polarity of
the batteries are correct.
MUCFH-13NV -
E4
MUCFH-18NV -
E3
2 Press the RESET button with tip end of ball point
pen or the like, and then use the remote controller.
RESET button
42
MUCFH-18NV -
E4
MUCFH-24NV -
E3