16
2) Simple Check Table for Main Parts
Part name
Test criteria
Tube temperature
sensor
Disconnect the connector and measure the resistance value with a tester. (Part temperature
10°C to 30°C)
Normal
Abnormal
NȍWRNȍ
Open or shorted
Room temperature
sensor
Disconnect the connector and measure the resistance value with a tester. (Part temperature
10 °C to 30 °C)
Normal .............
WRNȍEHWZHHQSLQV
Abnormal .........Open or shorted
Compressor
Disconnect the connector and measure the resistance values between the terminals with a
tester. (Coil temperature 10 °C to 30 °C)
Normal
Abnormal
Between each terminal
ȍWRȍ
Open or shorted
Blower fan motor
Ɣ
How to determine whether the DC motor has a malfunction
The following table shows the values for a healthy motor that was measured with a
multimeter.
The motor has a malfunction if any value is very different from the normal value.
Measurement method (pin number of P4 connector)
terminal
Tester -
terminal
Tester
measurement
mode
Normal value
Malfunction diagnosis
Pin 1 (red)
Pin 4
Resistance
,Q¿QLW\
Internal circuit of motor
broken
Pin 6 (white)
Pin 4
Resistance
VRINȍ
Internal circuit of motor
broken
Pin 7 (yellow)
Pin 4
Resistance
VRINȍ
Internal circuit of motor
broken
Pin 8 (blue)
Pin 4
Resistance
,Q¿QLW\
Internal circuit of motor
broken
Pin 4 (black)
Pin 1
Diode
0.5 V to 2 V
Internal circuit of motor
broken
Any pin
Outer casing
of motor
Resistance
,Q¿QLW\
Motor insulation
breakdown
The above is the diagnosis method for when the motor is isolated.
Regardless of the rotation state, do not test the motor when the connectors are connected.
Stepping motor
Measure the resistance value across terminals with a tester. (Part temperature: approx 25 °C).
Normal
Abnormal
Terminals 1-2
ȍWRȍ
Open or shorted
Terminals 1-3
Terminals 1-4
Terminals 1-5
Compressor
temperature
thermistor
Disconnect the connector and measure the resistance values between the terminals with a
tester. (Coil temperature 10°C to 30°C)
Normal
Abnormal
Between each terminal
ȍWRȍ
Open or shorted
Power supply board
¿QWKHUPLVWRU
Disconnect the connector and measure the resistance values between the terminals with a
tester. (Coil temperature 10°C to 30°C)
Normal
Abnormal
Between each terminal
ȍWRȍ
Open or shorted
Reactor
Disconnect the connector and measure the resistance values between the terminals with a
tester.
Normal
Abnormal
Between CN602 terminals
Continuity
Open
