The ambient temperature senor located at the center stay of the condensor detects ambient air temperature. It is a negative type thermistor whose resistance is inversely proportional to temperature. Its output is used for discharge temperature sensor, sensor fail-safe, temperature regulation door lock, blower motor level control, mix mode control and in-car humidity control
The ECM sets DTC B1237 if there is a short circuit in ambient temp sensor signal harness or the measured resistance value of sensor is less than threshold value(about 10.8㏀)
Item | Detecting Condition | Possible Cause |
DTC Strategy | ● Voltage check | ● Short circuit in harness ● Fault ambient temp.sensor ● Fault A/C Control Unit |
Threshold value | ● < 0.1V | |
Detecting time | ● 0.3sec | |
FAIL SAFE | ● Control with the vlaue of 20℃(67℉) |
Temperature(℃) | Resistance(㏀) | Temperature(℃) | Resistance(㏀) |
-30 | 507 | 25 | 30 |
-15 | 215.3 | 35 | 24.2 |
0 | 97.5 | 60 | 16 |
15 | 59.6 | 80 | 10.8 |
