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Home >> Saturn >> 1992 >> SC Standard >> Repair and Diagnosis >> External Pages >> Different car >> Section 12 (Engine Controls - System/Component Tests - 4.9L) >> Idle Control System (C-2) >> Idle Switch

Idle Switch

WARNING: This page is about a different car, the 1995 Cadillac DeVille. However, it is still accessible from the selected car via links, so may be relevant.
  1. The ISC motor is equipped with an internal idle switch (also called a throttle or nose switch) which informs the PCM when it should be controlling idle.
  2. Disconnect ISC connector. Connect an ohmmeter across Pink and Black/White wire terminals ("A" and "B") of ISC motor connector. See Fig 1 . With throttle closed, continuity should exist. With throttle open enough to relieve tension from the ISC plunger, continuity should not exist.
Fig 1: Idle Speed Control Solenoid/Idle Switch Schematic
G90E13213Courtesy of GENERAL MOTORS CORP.