Sunload Sensors
WARNING: This page is about a different car, the 2002 Oldsmobile Aurora. However, it is still accessible from the selected car via links, so may be relevant.
The sunload sensor assembly houses both the driver's and passenger's side sensors, and is located on each side of defrost grille. The sensor assembly provides the Instrument Panel Module (IPM) with the amount of sun light entering the vehicle through the driver's and passenger's side of windshield. A reference signal is sent from the IPM to the sunload sensor. A variable photo-diode resistor inside the sensor varies the voltage. The varied voltage provides a separate driver and passenger signal to the IPM. The sunload sensor also provides an average reading for the twilight sentinel feature. The remaining voltage is sent back to the IPM, providing input from the sensor.