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EATC System Functional Test

WARNING: This page is about a different car, the 1994 Mercury Sable, 1994 Lincoln Continental, and 1994 Ford Taurus. However, it is still accessible from the selected car via links, so may be relevant.
NOTE: Perform this test if EATC self-diagnostic test showed no error codes and fault is present.
  1. Ensure engine is cold and in-vehicle temperature is greater than 50°F (10°C). Turn ignition on. Press AUTOMATIC button and set temperature to 90°F. If EATC control panel lights, go to next step. If EATC control panel does not light, go to DIAGNOSIS WHEN EATC SELF-DIAGNOSTICS INDICATE NO ERRORS FOUND  .
  2. Verify blower motor does not come on with engine temperature less than 120°F (49°C). If blower motor does not come on, go to next step. If blower motor comes on, go to COLD ENGINE LOCK-OUT SWITCH INOPERATIVE test under BLOWER SPEED CONTROLLER & HIGH-SPEED BLOWER RELAY  .
  3. Start engine. Ensure coolant temperature is greater than 120°F (49°C). Set temperature display to 75°F. If blower motor comes on, go to next step. If blower motor does not come on, go to NO BLOWER test under BLOWER SPEED CONTROLLER & HIGH-SPEED BLOWER RELAY  .
  4. Rotate blower speed knob fully down. If blower motor goes to low speed, go to next step. If blower motor does not go to low speed, go to NO BLOWER test under BLOWER SPEED CONTROLLER & HIGH-SPEED BLOWER RELAY  .
    NOTE: Before going to step 5), check battery voltage. If voltage is less than 10 volts, check charging system.
  5. Rotate blower knob fully up. If blower motor goes to high speed, go to next step. If blower motor does not go to high speed, go to BLOWER SPEED CONTROLLER & HIGH-SPEED BLOWER RELAY  .
  6. Press defrost button. Verify air is discharged from defroster nozzle, with a small amount of air bled through side window demisters. Also, verify fresh/recirculated air door is in fresh air position. If air discharge and fresh/recirculated air door position is correct, go to next step. If air is not discharged through defroster or side window demisters, go to VACUUM SYSTEM TEST  .
  7. Press FLOOR button. If air is discharged through floor air ducts, go to next step. If air discharge is not through floor air ducts, go to VACUUM SYSTEM TEST  .
  8. Press VENT button. If air discharge is through panel ducts, go to next step. If air discharge is not through panel ducts, go to VACUUM SYSTEM TEST  .
  9. Ensure ambient temperature is more than 40°F (4°C). Press MAXA/C button. If fresh/recirculated air door is in recirculated air position, go to next step. If door is not in recirculated air position, go to VACUUM SYSTEM TEST  .
  10. Press VENT button. If VENT display is lit and A/C compressor clutch turns off, go to next step. If A/C compressor clutch remains on, go to A/C COMPRESSOR CLUTCH DOES NOT DISENGAGE WHEN IN OFF POSITION  .
  11. Press MAX A/C button again. If MAX A/C lights up and A/C compressor clutch comes on, go to next step. If A/C compressor clutch remains off, go to NO A/C COMPRESSOR CLUTCH OPERATION  .
  12. Press AUTOMATIC button. If AUTOMATIC button lights, test is complete. If AUTOMATIC button does not light, go to DIAGNOSIS WHEN EATC SELF-DIAGNOSTICS INDICATE NO ERRORS FOUND  .
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