General Information

B1242 Evaporator Sensor Open (High)

General Information

Component Location





General Description

The Evaporator sensor located on the HVAC unit and detects the evaporator core temperature. It is a negative type thermistor whose resistance is inversely proportional to temperature. The Evaporator sensor converts the measured temperature into a voltage value and delivers it to A/C ECU. When core temperature is blow threshold value, A/C ECU interrupts compressor relay power, in order to prevent evaporator freezing by excessive cooling.

DTC Description

DTC B1242 sets if Evaporator sensor signal is at or over 4.9 V for 0.3 seconds.

DTC Detecting Condition





Specification

** Resistance value of evaporator sensor as a function of temperature.






Diagnostic Circuit Diagram