heater air from front air ducts

[ZiggyPA]

How is this supposed to work exactly? The only way I can get those 4 to blow air is in economy mode below 70 degrees?
When I raise the temperature the air automatically goes to the windshield.
Also how do you select air to the foot space?

[chevygirl_2004]

This may not be much help but I'll tell you what we have to do. every once in a while our car will switch over windshield too. we have to take it out of auto and manually turn it back to vent with the air flow button on the controls. That may not help but you can try. With ours one of the motors is out on the dampers doors and the passenger side will blow cold air in the winter. we have to drop the glove box down and manually move the door so I can have heat. Other than leaving the temp control off auto Im not sure what else to do with it.

[ZiggyPA]

I think you have a newerl model PA, I can't select these options.
I fiddled with the controls in park, 'heater' selects the foot space.
Can't get the dashboard vents to work in any mode though. Earlier this night they did only work in economy between 60-70.
Also when I select 'auto' it selects 'economy' does this has to do with the exterior temperature being below 30 ?

[HotZ28]

The auto climate control is a very complex system. What direction the airflow follows, depends on a network of sensors to the programmer & set points on the controller. Some of the sensors used to determine airflow are; outside & inside temp and the sun sensor. Have you ever noticed how when the car is in direct sunlight, the airflow will increase to the dash vents? You can fool the sun sensor on the dash with a bright (LED) type light, to see if airflow will change, however. at night & in cold weather, it is nearly impossible to get airflow from the dash vents. In addition, the A/C compressor will not engage when below 50 deg. All indications are, your system is working as designed. When in AUTO mode, airflow should change slightly, based on inside/outside temp & sunlight, or darkness!

[ZiggyPA]

Thanks, that is good to know. It was indeed dark outside when I tested it.
Too bad this kind of information isn't in my owners manual. I had no idea this system was so advanced...

[HotZ28]

In an effort to clarify post #4 for other members who view this thread, the discussion above covers pre-96 PA’s with auto climate control. This system was improved in 1996 to included some additional features that allow an owner to manually adjust air-flow from defrost, to mid level, or to bottom (heat) vents, regardless of temp/light sensor inputs. Another improvements included the addition of a bi-level switch.

In addition, the auto climate control system has gone through a continuous year-to-year improvement process, since first designed by Cadillac and introduced in 1964.