Mitsubishi MCFH-13NV Service Manual page 51

Check of outdoor thermistor
H
Thermistors in the outdoor unit are abnormal.
w Disconnect the connectors CN661 and/or CN662 from the deicer P.C. board.
(Check the characteristics of each thermistor.)
Defrost thermistor(RT61)
Turn OFF the
power supply.
Ambient temperature
thermistor(RT63)
Measure
resistance
between CN 662
3 and 4.
Measure
resistance
between CN 661
1 and 2.
Does the resistance
of thermistor have
the characteristics
on page 33?
Replace the
thermistor.
Reconnect CN661
and CN662.
Turn ON the power
Yes
supply and press
the EMERGENCY
OPERATION
switch.
No
W1. It is thought defective contact of the connector.
51
Replace the deicer P.C.
board.
No
Does the unit operate
10 minutes or more?
Yes
Ok W1.