Humidity sensor located at center fascia detects in-car humidity for in-car humidity control. Humidity sensor and incar sensor are joined as one body. Humidity sensor transforms measured humidity into frequency value and delivers it to A/C Control unit. If ambient air temperature or in-car humidity is in a specified range that can makes frost on the windowglass, A/C will be activated to control in-car humidity to prevent frost on the windowglass.
The ECM sets DTC B1201 if there is a short circuit in humidity sensor signal harness.
Item
Detecting Condition
Possible Cause
DTC Strategy
? Voltage check
? Open Circuit in power harness
? Faulty Humidity Sensor
? Faulty A/C control unit
Threshold value
? > 3.13V
Detecting time
? 0.3sec
FAIL SAFE
? Control with the value of 10%
? Voltage value of humidity sensor as a function of humidity.
Humidity(%)
Frequency(Hz)
30
3.13
65
1.29
35
3.07
70
1.12
40
2.94
75
1.05
45
2.67
80
1.01
50
2.35
85
0.99
55
2.01
90
0.94
60
1.54