Auxiliary Intake Air Control Solenoid Inspection w/o Scan Tool

The auxiliary intake air control solenoid is operated by the powertrain control module (PCM). The PCM supplies a ground path to the solenoid control circuit using an internal solid state device called a driver. When the PCM commands the solenoid ON, the voltage on the control circuit should be near zero or low. When the PCM commands the solenoid OFF, the voltage on the control circuit should be near battery voltage or high. When the solenoid is energized, manifold vacuum is applied to the vacuum motor and the auxiliary inlet air duct door is closed.

CAUTION: Refer to Fuel Vapors in Evaporative Emission (EVAP) Components Caution in Cautions and Notices.
Fig 1: Intake Air Control Solenoid
Courtesy of GENERAL MOTORS CORP.
1. Disconnect the electrical connector of the intake air control solenoid.
2. Use a DMM in order the measure the solenoid resistance value.

   Specification:  The resistance should be between 37-44 ohms at 20°C (68°F).

3. Replace the solenoid if the resistance is not within the specified range. Refer to Auxiliary Intake Air Control Solenoid Replacement .
Fig 2: Checking Continuity Between Solenoid Terminal And Solenoid Housing
Courtesy of GENERAL MOTORS CORP.
4. Use a DMM in order the check for continuity between each solenoid terminal and the solenoid housing.

   Specification:  The DMM has to read infinite (OL).

5. Replace the intake air control solenoid if the resistance is not within specification. A shorted solenoid may cause damage to the PCM.
Fig 3: Air Passing Through Inboard Intake Air Control Solenoid
Courtesy of GENERAL MOTORS CORP.
6. Blow air through the inboard port of the intake air control solenoid. Air has to flow freely through the vent port and NOT out of the outboard port.
7. Replace the solenoid if either of the following conditions is observed. Refer to Auxiliary Intake Air Control Solenoid Replacement .
   • Air flows from the inboard port out through the outboard port.
   • Air does not flow from the inboard port out through the vent port.
Fig 4: Auxiliary Intake Air Control Solenoid Test
Courtesy of GENERAL MOTORS CORP.
8. Apply battery voltage across the solenoid terminals.
9. Blow air through the inboard port of the solenoid. Air should flow through the solenoid and out of the outboard port.
10. Replace the solenoid if the solenoid fails any of the tests. Refer to Auxiliary Intake Air Control Solenoid Replacement .
11. Connect the electrical connector of the intake air control solenoid.
12. Start the engine.
13. Inspect that the intake air control solenoid is ON.
14. If the solenoid is not energized, disconnect the solenoid electrical connector and connect a test lamp across the terminals of the solenoid circuit.
15. If the test lamp illuminated, replace the solenoid. Refer to Auxiliary Intake Air Control Solenoid Replacement .
16. If the test lamp did not illuminate, inspect for the following conditions:
    • Inspect for an open in the ignition positive voltage supply to the solenoid.
    • Inspect for an open or a short to voltage in the solenoid control circuit.
17. Repair any electrical circuit conditions as necessary. Refer to Wiring Repairs in Wiring Systems.
18. If you did not find and repair an electrical condition, replace the PCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.