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Test C: Air RECIRCULATION Malfunction

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  1. Perform SYSTEM OPERATION CHECK  under TROUBLE SHOOTING. Go to next step.
    2. NOTE: This step tests for a inoperative mode actuator in one mode position or in the wrong mode positions.
  2. Turn ignition on. Place the blower control to the highest speed position. Place the mode control to each position. Does the mode actuator operate correctly for each mode position? If so, go to next step. If not, go to TEST A: AIR DELIVERY IMPROPER .
    3. NOTE: This step tests for a inoperative recirculation actuator in one mode positions or in the wrong mode positions.
  3. Place the mode control to the floor position. Press the REC switch ON. Press the OSA switch ON. Does the air inlet actuator operate correctly for each mode position? If so, go to next step. If not, go to step  7.
    4. NOTE: This step tests for an A/C system performance that is correct for the present conditions that would mandate a state of automatic recirculation mode being active. The automatic recirculation mode becomes active when the high side pressure reaches 320-380 psi (2206-2620 kPa). The mode remains on until the high side pressure drops below 210-270 psi (1447-1861 kPa). In automatic recirculation mode their will be no indication on the HVAC controller that the mode is active, the out side air (OSA) and recirculation (REC) switches and indicators will be inoperative on the HVAC controller.
  4. Perform the A/C system performance test. See A/C SYSTEM PERFORMANCE TEST  under PERFORMANCE TESTS. Does the high side pressure reading indicate a condition in the A/C system which requires operation in the AUTOMATIC RECIRCULATION mode? If so, go to next step. If not, go to step  6.
  5. Repair or replace the failed component. After repairs are complete, go to step  17.
  6. Start the engine. Place the mode control to the VENT position. Press the A/C switch on. Press the REC switch on. Press the OSA switch on. Does the recirculation actuator operate correctly for each mode position? If so, check for intermittent and poor connections. If not, go to next step.
  7. Check the recirculation actuator ignition 3 voltage circuit for an open or high resistance. Did you find and correct the condition? If so, go to step  17. If not, go to next step.
  8. Check the actuator ground circuit for an open or high resistance. Did you find and correct the condition? If so, go to step  17. If not, go to next step.
  9. Verify the recirculation door is in the RECIRCULATION mode position. Disconnect the connector to the A/C high pressure recirculation switch. Does the recirculation door move to the OUTSIDE AIR mode position? If so, go to next step. If not, go to step  11.
    10. NOTE: This step tests for a internally shorted A/C high pressure recirculation switch causing the automatic recirculation mode to be active.
  10. Turn ignition off. Measure for continuity through the A/C high pressure switch. Is continuity present? If so, go to step  15. If not, go to next step.
  11. Check the output signal circuit to the high pressure cut-off switch on the secondary A/C refrigerant for a high resistance or for a short to ground. Did you find and correct the condition? If so, go to step  17. If not, go to next step.
  12. Check the recirculation actuator control circuit for an open short to ground or short to voltage. Did you find and correct the condition? If so, go to step  17. If not, go to next step.
  13. Inspect PCM for poor connections. Did you find and correct the condition? If so, go to step  17. If not, go to next step.
  14. Replace and reprogram the VCM or the PCM. See POWERTRAIN CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in REMOVAL, OVERHAUL & INSTALLATION article in ENGINE PERFORMANCE. After repairs are complete, go to step  17.
  15. Inspect secondary A/C refrigerant high pressure switch for poor connections. Did you find and correct the condition? If so, go to step  17. If not, go to next step.
  16. Replace the A/C high pressure recirculation switch. See A/C HIGH PRESSURE SWITCH  under REMOVAL & INSTALLATION. After repairs are complete, go to next step.
  17. Operate the system in order to verify the repair. Did you correct the condition? If so, system is okay. If not, go to step  2.
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