I cant turn my ac/ heater control knobs The ac actually runs but all the cold air either goes to the floot or on the windhield. The selector knob wont turn so I cant select heat or ac....luckily its stuck half way for summer but its still very hot in the car with the ac on your feet. I am trying to find the control box? control head? but I dont know the nomenclature. I have found a few sites on the 'net but they arent toll-free. I dont want to send away for something and get the wrong item and waste money on shipping the werong stuff. Thanks for any help!

Air Flow Control
Air flow control is accomplished in the following manner:

• Primary control is through the function selector knob , mounted on the heater function selector switch, which is part of the heater control .
• The function selector knob has the following positions: OFF, PANEL, PANEL/FLOOR, FLOOR, FLOOR/DEFROST and DEFROST.
• The heater function selector switch combines a vacuum selector valve with an internal electrical switch.

• The vacuum selector valve directs source vacuum to various vacuum control motors (18A318) . Refer to the System Airflow Schematic and Vacuum Control Charts.
• An internal single-pole electrical switch is also controlled by the selector. The switch controls the electrical supply to the heater blower motor switch (18578) .
• The position of the function selector knob determines the manner in which the system will operate.
• Each position of the function selector knob is detented for positive engagement.
• You probably have a vacuum leak , Pull heater control panel an check for vacuum . A broke vacuum hose or The vacuum selector valve is bad ! Or check for a vacuum hose in the engine compartment being off somewhere !
  

. Air won't blow out of the floor or center vents just defrost ? Do you have manual or automatic climate control ?
Air Flow Control
Air flow control is accomplished in the following manner:

• Primary control is through the function selector knob mounted on the A/C-heater function selector switch, which is part of the integrated control panel.
• The function selector knob has the following positions: OFF, MAX A/C, A/C, PANEL, PANEL/FLOOR, FLOOR, FLOOR/DEFROST and DEFROST. The A/C-heater function selector switch combines a vacuum selector valve with an internal electrical switch.
• The vacuum selector valve directs source vacuum to various vacuum control motors (18A318). Refer to the Vacuum Control Diagram , System Airflow Schematics and Vacuum Control Chart .
• Two internal, single-pole electrical switches are also controlled by the A/C-heater function selector switch. The combination of these electrical switches controls the electrical supply to the A/C clutch and heater blower motor switch (18578).
• The position of the function selector knob determines the manner in which the system will operate.
• Each position of the function selector knob is detented for positive engagement.
• Vacuum Control Motors The vacuum control motors (18A318):
  
  • are located on the A/C evaporator housing, A/C recirculation air duct and heater air plenum chamber (18471).
  • direct system airflow to the vehicle interior as determined by the remote climate control module or manual override.
  • The five-passenger seating configuration has an additional vacuum control motor mounted on the heater air plenum chamber to control airflow to the rear seat A/C register (19893).
  
  

The sliding switch on the console is stuck in the cold position and the knob is pulled off. Use pliers to jiggle the switch as best you can. Feel under the center console and you probably will find the cable that is hooked up to the flapper. You'll know because when you jiggle the cold/heater switch at the upper console, the cable will move slightly. At the hookup of the cable to the flapper down under the console (passenger side) try to work the flapper loose to the open (or close) position. At the same time work the sliding switch (with pliers). The flapper will come loose and function properly. Try not to knock of the AC button like I did in the process. It flew off some where under the passenger seat. I'll find it sometime before summer. Ha.

You have a broken mounting at the end of the cable,at the housing thats why the temp. control knob doesnt work,you can remove the center console to gain access to pivot the broken piece manually and try to modify it so you can attach the cablr

You need to repair the heater core with a soldering gun.

If you do not have heat, or only have heat, IMHO it is most likey the AC/heater control unit. This is the part which has the AC/heat control buttons and knobs.

Easy Diagnosis:
The easiest way to verify this is to turn on the radio, press and hold the power on/off button and press and hold the scan-up button for a second (full second). The word "A/C TEMP" should appear on the left of the display and a number from 0 to 16 on the right. I suspect yours will have the number 0 (or 16 if heating only problem) displayed no matter where you turn the temperature control knob. If this is the case you could turn the temp. knob to full heat and see if it goes to 16 after pushing down or to the right on the knob.
In a working system, the number moves evenly in increments of 1, from 0 to 16 as you turn the temperature knob.

Easy Fix:
I was able to take mine out and solder 3 loose connections to fix it.

The beginning steps are the same as for any radio removal procedure and check for loose connections.

hI THEGROVE45, did you ever get this problem fixed. I have the same problem, and took it into the dealership, they told me they would have to replace the whole unit, and told me the light inside there was not a light bulb but a wand lit up with LED.

Is the heater working? Turn the A.C. off with the car at an idle. Turn the A.C. on and listen for the compressor to turn on. (should hear a click under the hood and the motor should change pitch. If no noise, the compressor is not comming on. The o-rings were bad about leaking on these cars, letting out all the freeon. If there is no freeon, the low pressure switch won't let the compressor run.

it's either the blower motor switch or blower motor resister. Resistor ?Heater Blower Motor Switch Removal Remove the battery (10655) ; refer to Section 414-01 . Remove the battery tray. Remove the screws. Remove the battery tray. Disconnect the heater blower motor switch resistor connector. Remove the heater blower motor switch resistor (18591). Remove the two screws. Remove the heater blower motor switch resistor. ----------------------------------- Switches Removal Disconnect the battery ground cable. Remove the center trim panel; refer to Section 501-12 . Remove the control assembly. Remove the screws. Remove the control assembly. Remove the A/C-heater function selector switch knob. Disconnect the vacuum harness connector. Disconnect the A/C-heater function selector switch connector. Remove the A/C-heater function selector switch. Remove the screw. Remove the A/C-heater function selector switch. Remove the temperature control switch knob. Disconnect the temperature control switch connector. Remove the temperature control switch. Remove the screw. Remove the temperature control switch. Remove the heater blower motor switch knob. Disconnect the heater blower motor switch connector. Remove the heater blower motor switch (18578). Remove the screw. Remove the heater blower motor switch. ----------------------------

First, feel the heater hoses going into the firewall under the hood. If they are hot, then you have hot engine coolant going into the heater core. If they are not hot, then you either have a bad thermostat or you are very low on engine coolant.

Next you need air flowing through the heater core so it can come out heated through your vents. If the iar is flowing somewhere else, your temp blend door is not moving because the bend door motor is bad or your temp knob on your heater controls is bad. The blend door motor is an electric motor.

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Air Flow Control
Air flow control is accomplished in the following manner:

• Primary control is through the function selector knob , mounted on the heater function selector switch, which is part of the heater control .
• The function selector knob has the following positions: OFF, PANEL, PANEL/FLOOR, FLOOR, FLOOR/DEFROST and DEFROST.
• The heater function selector switch combines a vacuum selector valve with an internal electrical switch.

• The vacuum selector valve directs source vacuum to various vacuum control motors (18A318) . Refer to the System Airflow Schematic and Vacuum Control Charts.
• An internal single-pole electrical switch is also controlled by the selector. The switch controls the electrical supply to the heater blower motor switch (18578) .
• The position of the function selector knob determines the manner in which the system will operate.
• Each position of the function selector knob is detented for positive engagement.

Temperature Control
The temperature control operates in the following manner:

• Temperature control of the heater system is determined by the position of the temperature control knob (between COOL-BLUE and WARM-RED) of the heater control .
• This control knob is connected to a potentiometer mounted in the heater control . This potentiometer is electrically connected to the electric blend door actuator that operates the A/C air temperature control door.

• Movement of the control knob from COOL (Blue) to WARM (Red) causes a corresponding movement on the air temperature control door and determines the temperature that the system will maintain.

System uses a reheat method to provide conditioned air to the passenger compartment.

• All airflow from the blower motor (18527) passes through the A/C evaporator housing .
• Temperature is then regulated by reheating a portion of the air and blending it with the remaining cool air to the desired temperature.
• Temperature blending is varied by the air temperature control door, which regulates the amount of air that flows through and/or around the heater core (18476) , where it is then mixed and distributed.

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inside you plenum box:

IT SOUNDS LIKE WHEN TURNING THE KNOB IT WAS STIFF TO TURN THIS COULD BE CAUSED BY A SEIZED CABLE IF CABLE IS NOT SEIZED OPEN UP YOUR HOOD AND WHERE THE HEATER CABLE GOES THROUGH THE FIRE WALL THE CABLE SHOULD GO TO A FLAPPER WHICH IF PUSHED ONE WAY GIVES COLD AIR IF PUSHED THE OTHER WAY GIVES HOT AIR PUSH IN THE OPPOSITE DIRECTION TO WHAT IT IS NOW PUT A SMALL PAIR OF VISE GRIPS ON END OF CABLE SO IT CANT SLIP BACK TO COLD POSITION UNTIL YOU CAN GET A NEW KNOB IF CABLE IS SEIZED YOU WILL HAVE TO REPLACE CABLE+