Humidity sensor located at heater control unit 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 ● Short Circuit in signal harness ● Faulty Humidity Sensor ● Faulty A/C control unit |
Threshold value | ● < 0.1V | |
Detecting time | ● 10msec | |
FAIL SAFE | ● Control with the value of 10% |
※ Frequency value of humidity sensor as a function of humidity.
Humidity(%) | Frequency(Hz) | Humidity(%) | Frequency(Hz) |
0 | 7351 | 60 | 6600 |
10 | 7224 | 70 | 6468 |
20 | 7100 | 80 | 6330 |
30 | 6976 | 90 | 6186 |
40 | 6853 | 100 | 6033 |
50 | 6728 | ||
