CTS V8-5.7L VIN P (2004)
Solar Sensor: Description and Operation
SUNLOAD SENSOR
The sunload sensor is a 2-wire photo diode. The vehicle uses left and right sunload sensors. The 2 sensors are integrated into the sunload sensor
assembly along with the ambient light sensor. Low reference and signal circuits enable the sensor to operate. As the sunload increases, the sensor signal
decreases. The sensor operates within an intensity range between completely dark and bright. The sensor signal varies between 0-5 volts. The HVAC
control module converts the signal to a range between 0-255 counts. The sunload sensor provides the HVAC control module a measurement of the
amount of light shining on the vehicle. Bright, or high intensity, light causes the vehicles inside temperature to increase. The HVAC system compensates
for the increased temperature by diverting additional cool air into the vehicle. If the sensor is open or shorted, no sunload adjustment occurs and the
SERVICE A/C SYSTEM message is displayed.