Solar Sensor: Description and Operation

Right And Left Sun Load Sensors (Typical):

The sun load sensors are light sensitive photo-diodes which monitor the heat load of the sun on the vehicle. There are two sun load sensors utilized by the dual zone (CJ2) A/C system, one right and one left. The sensors are located on top of the instrument panel, one on each side, mounted under the defroster grill where sunlight can reach them. The Pontiac system (C68) uses only one sun load sensor.

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