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Home >> Pontiac >> 1992 >> Firebird Base, 2D Convertible, 3.1 T, Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 11 (Engine Controls - System/Component Tests) >> Idle Control System (C-2) >> Engine Controls - System/Component Tests >> Idle Air Control (IAC) Motor
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Idle Air Control (IAC) Motor

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  1. Disconnect harness connector to motor. Check resistance across IAC coil terminals "A" and "B" (B coil) and "C" and "D" (A coil). Resistance should be 40-80 ohms. See Fig 1 . If resistance is as specified, go to next step. If resistance is not as specified, replace IAC motor.
  2. Check resistance between IAC terminals "B" to "C" and "A" to "D". Resistance should be infinite. If resistance is not as specified, replace IAC motor.
NOTE: Additional testing of Idle Air Control (IAC) motor requires an IAC motor actuator and node light, or a "Scan" tester capable of cycling ECM output devices (General Motors Tech 1).
Fig 1: Typical IAC Motor Circuit
G91E07428Courtesy of GENERAL MOTORS CORP.
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