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Home >> Cadillac >> 2003 >> CTS Standard >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Diagnostic Tests >> DTC P0660: Intake Manifold Tuning Valve Control Circuit Malfunction >> Test Description
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Test Description

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

  1. 2

    Listen for an audible click when the Intake Manifold Tuning (IMT) solenoid operates. Command both the ON and OFF states. Repeat the commands as necessary.
  2. 4

    Tests for voltage at the coils side of the IMT solenoid. The manifold fuse supplies power to the coil side of the IMT solenoid.
  3. 5

    Verifies that the ECM is providing ground to the IMT solenoid.
  4. 6

    Tests if ground is constantly being applied to the IMT solenoid.