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Home >> Cadillac >> 2003 >> CTS Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P2100: Throttle Control System - Excessive Pulse Width Modulation Detected >> Test Description
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Test Description

The numbers below refer to the step number in the diagnostic procedure.

  1. 3

    The throttle valves are spring loaded in a slightly open position and should move in either direction without binding. The throttle valves should always be under spring pressure.
  2. 6

    When the ignition is turned ON, the ECM operates the throttle control motor to verify the integrity of the system prior to start-up. This can be seen by the momentary flash of the test lamp as the ignition is turned ON.