Mitsubishi SUZ-KA35VA Service Manual page 90

h Check of R.V. coil
First of all, measure the resistance of R.V. coil to check if the coil is defective. Refer to 12-4.
In case CN721 is not connected or R.V. coil is open, voltage is generated between the terminal pins of the connector
although any signal is not being transmitted to R.V. coil.
Check if CN721 is connected.
Unit operates COOL mode even if it is set to HEAT mode.
Disconnect connector (CN61)
between the compressor and the
intelligent power module.
Turn ON the power supply and press
EMERGENCY OPERATION switch
twice (HEAT mode).
Unit operates HEAT mode even if it is set to COOL mode.
Disconnect connector (CN61)
between the compressor and the
intelligent power module.
Turn ON the power supply and
press EMERGENCY OPERATION
switch once (COOL mode).
i Check of outdoor fan motor
Check the connection between the
connector CN931 and CN932.
Is the resistance between each ter-
minal of outdoor fan motor normal?
(Refer to 12-4.)
No
(Fixed to either 5 or 0 VDC)
Replace the outdoor fan motor.
OC322G
[SUZ-KA25/35VA(H)R1.TH
Is there 230 VAC between CN721
on the inverter P.C. board 3 minutes
after the power supply is turned ON?
Yes
Replace the 4-way valve.
Is there 230 VAC between CN721
on the inverter P.C. board 3 minutes
after the power supply is turned ON?
No
Replace the 4-way valve.
Yes
Disconnect CN932 from outdoor electronic control P.C. board or
the inverter P.C. board, and turn on the power supply.
Rotate the outdoor fan motor manually and measure the voltage
of CN931.
Between 1(+) and 5(-)
Between 2(+) and 5(-)
Between 3(+) and 5(-)
Does the voltage between each terminal become 5 and 0
No
VDC repeatedly?
Does the outdoor fan motor rotate smoothly?
No
Replace the outdoor electronic control P.C. board or the inverter
P.C. board.
90
SUZ-KA50VAR2.TH]
and
Replace the inverter
No
P.C. board.
and
Replace the inverter
Yes
P.C. board.
Yes
Yes