The Evaporator sensor is a negative temperature coefficient thermistor that is mounted at the evaporator core. The A/C ECU uses the evaporator sensor data to control A/C compressor operation in order to prevent evaporator freezing.
Air conditioner Control Module sets DTC B1242 if Evaporator sensor has been detected over 4.9V for 4 seconds
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Voltage check |
•
Open in signal circuit
•
Short to battery in signal circuit
•
Faulty Evaporator sensor
•
Faulty Air conditioner control Unit |
Enable Conditions |
•
IG KEY ON | |
Threshold value |
•
Evaporator sensor has been detected over 4.9V for 0.3 seconds | |
Failsafe |
•
Control with the value of -2℃(28.4℉) |
Temperature(℃/℉) | Resistance(㏀) | Temperature(℃/℉) | Resistance(㏀) |
-10/-14 | 18 | 20/68 | 4.8 |
0/32 | 11 | 30/86 | 3.3 |
10/50 | 7.3 | 40/104 | 2.3 |
