For 1990-2009 cars

The sun load sensors (1) are light sensitive photo-diodes. These diodes monitor the heat load of the sun on the vehicle. The 2 sun load sensors are utilized by the dual zone (CJ2) A/C system.

The sensors are located on top of the instrument panel. There is 1 sensor on each side of the IP, mounted under the defroster grille (2).

The Pontiac system (C68) uses only 1 sun load sensor.

The heater and A/C programmer compares the sun load sensor readings to the inside temperature reading. This determines how much cooling is required in order to reach and maintain the desired temperature setting on each side of the vehicle.

In order to ensure proper operation of the sun load sensor, do not cover or obstruct the flow of sunlight to the sensor.