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Home >> Saab >> 1993 >> 900 S, 2D Convertible, Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - System/Component Tests >> Idle Control System >> Engine Controls - System/Component Tests >> Idle Air Control (IAC) Valve (9000 Turbo)
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Idle Air Control (IAC) Valve (9000 Turbo)

  1. Connect ISAT scan tester following manufacturer's instructions. Enter command code 3021. Listen for sound of IAC valve operating. If valve buzzes, go to next step. If valve does not buzz, go to step 3).
    NOTE: Engine cannot be started until 12 minutes have elapsed. If engine must be started sooner, enter command code FF00 to clear the function.
  2. Disconnect hoses from IAC valve, located near center of air intake duct. Unplug IAC valve connector. Valve slide should close completely, then open slightly to limp-in position. If operation is not as specified, replace IAC valve.
  3. Reconnect wiring to IAC valve. Measure resistance between pin No. 87 of main relay (Blue/Red wire) and pin No. 49 of ECM (Blue/Red wire). If resistance is about 4 ohms, go to next step. If resistance is not as specified, repair appropriate Blue/Red or Blue/White wires from IAC valve connector. See WIRING DIAGRAMS article in this section. If wires are okay, temporarily substitute known good IAC valve. Retest system.
  4. With ignition off, connect breakout box to ECM and vehicle harness. Turn ignition on. Enter command code 3021. Unplug IAC valve connector. Check for battery voltage between connector terminal No. 1 (Blue/White wire) and pin No. 24 (Blue/Red wire) of ECM. If battery voltage exists, go to next step. If battery voltage does not exist, repair appropriate wire. If wiring is okay, check main relay. See RELAYS  under MODULES, RELAYS & SOLENOIDS.
  5. Turn ignition off. Unplug wiring from ECM. Check Blue/Red wire between IAC valve and ECM pin No. 49 for open or short. Repair as necessary. If wire is okay, erase trouble code and drive car to see if problem occurs again.
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