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Home >> Pontiac >> 1971 >> GTO Base, 6.6L Eng, Eng CD WS, Automatic Trans >> Repair and Diagnosis (Single Page) >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> Automatic Temperature Control >> Testing >> Functional Test
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Functional Test

NOTE: Perform tests in order shown. Allow time between steps for programmer to function and system to stabilize.
  1. Set Selector Lever at OFF and Temperature Dial to MAX HEAT.
    1. Blower runs at low speed, warm air from heater outlet only.
    2. Assures of: Low blower, sealed defroster, open water control valve, compressor not running.
  2. Move Selector Lever to VENT.
    1. Blower speed remains low, cool air from A/C outlets.
    2. Assures of: Low blower, A/C mode, minimum temperature, closed water valve, compressor not running.
  3. Move Selector Lever to LO.
    1. Blower remains at low and airflow is from heater outlet or heater and A/C outlets (depending on ambient temperature). Air temperature slightly increased from that in step  2).
    2. Assures of: Low blower, mode control, temperature control, compressor running.
  4. Move Temperature Dial to MAX COLD.
    1. Blower remains at low and air flow is from A/C outlet or A/C and heater outlets. Air temperature is lower than in step 3).
    2. Assures of: Low blower, mode control control, compressor is running.
  5. Move Selector Lever to AUTO.
    1. Blower speed increases. Airflow and temperature same as in step 4).
    2. Assures of: Blower control, temperature control, mode control, compressor is running.
  6. Move Temperature Dial to MAX HEAT.
    1. Blower speed decreases, then increases while Temperature Dial is being moved. Air flow from heater outlet or heater and A/C outlets at increased temperature from step 5).
    2. Assures of: Blower control, mode control, temperature control, compressor is running.
  7. Move Selector Lever to HI.
    1. Blower speed increases to high. Airflow and temperature remain same as in step 6).
    2. Assures of: High blower, mode control, temperature control, compressor is running.
  8. Move Selector Lever to DEFOG.
    1. Blower speed decreases slightly. Airflow is from heater and A/C outlets (bi-level). Temperature remains warm.
    2. Assures of: Bi-level mode, blower control, temperature control, compressor is running.
  9. Move Temperature Dial to MAX COLD.
    1. Blower speed decreases, then increases while Dial is being moved. Air temperature decreases, airflow remains bi-level.
    2. Assures of: Bi-level mode, blower control, compressor is running.
  10. Move Selector Lever to DEICE.
    1. Blower speed same as in step 7). Airflow remains cool and is from defroster nozzles.
    2. Assures of: High blower, DEICE mode, temperature control, compressor is running.
  11. Move Temperature Dial to MAX HEAT.
    1. Blower speed and air flow same as step 10), air temperature increases.
    2. Assures of: High blower, DEICE mode, temperature control, compressor is running.
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