EN - 51
EN - 50
Failure Diagnosis
Method of Checking Sensor Characteristics
(1) Pressure (Low, Intermediate, Unit outlet, High pressure) sensor
While the connector is inserted to the control PCB, measure the voltage and check if the pressure is normal by
using the table below.
< Relationship between sensor output voltage and pressure >
Pressure (MPa)
0.00
1.00
2.00
3.00
4.00
5.00
6.00
7.00
8.00
9.00 10.00 11.00 12.00
Voltage (DCV)
0.50
0.77
1.03
1.30
1.57
1.83
2.10
2.37
2.63
2.90
3.17
3.43
3.70
* In the table above, when the pressure value is an intermediate value such as 4.5MPa, use a proportional
calculation.
When checking the voltage of a pressure sensor, always use DCV range of the tester.
Use caution, measurement by using resistance range may cause a sensor failure.
(2) Suction gas temperature sensor, Gas cooler outlet temperature sensor
Measure the resistance while the connector is disconnected from the control PCB, and check if the temperature is
normal by using the following table.
< Relationship between sensor temperature and resistance value >
Temperature
(°C)
-50
-40
-30
-20
-10
0
10
20
30
Resistance
value (kΩ)
77.58 43.34 25.17 15.13 9.39 6.00 3.94 2.64 1.82
* In the table above, when the temperature is an intermediate value such as -5 °C, use a proportional calculation.
(3) Discharge gas temperature sensor
Measure the resistance while the connector is disconnected from the control PCB, and check if the temperature is
normal by using the following table.
< Relationship between sensor temperature and resistance value >
Temperature
(°C)
20
30
40
50
60
70
80
90
100
110
120
Resistance
value (kΩ)
70.13 45.05 29.67 20.00 13.79
9.71
6.97
5.09
3.77
2.84
2.16
* In the table above, when the temperature is an intermediate value such as 65 °C, use a proportional calculation.
(4) Other temperature sensors (unit outlet, ambient, split outlet temperature.)
Measure the resistance while the connector is disconnected from the control PCB, and check if the temperature is
normal by using the following table.
< Relationship between sensor temperature and resistance value >
Temperature
(°C)
-10
0
10
20
30
40
50
60
70
Resistance
value (kΩ)
26.22
15.76
9.76
6.21
4.05
2.70
1.84
1.28
0.90
* In the table above, when the temperature is an intermediate value such as 35 °C, use a proportional calculation.
Caution
[Voltage measurement method]
Contact the tester lead
to the terminal.
[Resistance measurement
method]
Contact the tester lead
to the terminal.
[CR2-EN-PCB]
H
P
3P1
3P2
3P
3
3P
4
LP
IP
U
O
P
3
3
1
1
1
1
3
3
Red lead (+) of the tester
Red lead (+) of the tester
Red lead (+) of the tester
Black lead (-) of the tester
Black lead (-) of the tester
Black lead (-) of the tester
Red lead (+) of the tester
Black lead (-) of the tester
01_OCU-CR1000VF8A.indd 50
2019/08/27 10:56:10
