2003 Cadillac CTS Owner's Manual - Page 225

(Passenger's Temperature Switch): This switch is used to increase or decrease the temperature of the air for the passengers independent of the driver's setting. To turn the system on, press the PWR button located on the passenger's side of the climate control panel. To adjust the temperature, press the up or down arrow on the PWR button. The temperature will increase or decrease with each press of an arrow. If the passenger's temperature switch is off, the driver's temperature switch controls the temperature for the entire vehicle. The passenger's side temperature is only displayed when the passenger's side temperature switch is on. Automatic Operation AUTO (Automatic Climate Control): This button is used to select the automatic operation of the climate control system. When the automatic operation is active, AUTO will appear next to the fan and mode settings on the display. There are three sensors in the climate control system. One monitors the sun's solar radiation, another monitors temperature of the air inside the vehicle, and a third monitors the temperature outside the vehicle. The climate control system will vary the fan speed, air delivery mode and use of the air conditioning compressor to maintain the set temperature based on the information received from these sensors. See "Driver's Temperature Switch" and "Passenger's Temperature Switch" listed previously for more information on setting a temperature. To find your comfort zone, start with the 75_F (24_C) setting and allow approximately 10 to 30 minutes for the system to regulate. Adjust the temperature if necessary. If you choose either the lowest temperature setting, 60_F (16_C), or the highest temperature setting, 90_F (32_C), the system will not cool or heat any faster, but the system will stay at that setting without regulating fan speed. To avoid blowing cold air in cold weather, the system will start at lower fan speeds until warm air is available. The length of reduction depends on the outside air temperature, engine coolant temperature or the time since the engine was last started. As the engine coolant warms up, the fan speed will gradually increase. 3-4