The Evaporator sensor is located on the AC/heater boxand it detects the evaporator core temperature. When the core temperature is below the threshold value, the A/C ECU interrupts the compressor relay in order to prevent evaporator freezing.
DTC B1242 sets if Evaporator sensor signal is at or over 4.9V for 0.3 seconds.
Item | Detecting Condition | Possible Cause |
DTC Strategy |
•
Voltage check | 1. Open in signal circuit. 2. Short to battery in signal circuit. 3. Faulty Evaporator sensor. 4. Faulty Air conditioner control Unit. |
Enable Conditions |
•
Ignition ON | |
Threshold value |
•
Evaporator sensor signal is at or over 4.9V for 0.3 seconds. | |
Failsafe |
•
Control with the value of -2℃(28.4℉) |
※ Resistance value of evaporator sensor as a function of temperature.
Temperature(℃/℉) | Resistance(㏀) | Temperature(℃/℉) | Resistance(㏀) |
-10/-14 | 43.3 | 20/68 | 12.1 |
0/32 | 27.6 | 30/86 | 8.3 |
10/50 | 18 | 40/104 | 5.8 |
