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Home >> Cadillac >> 2003 >> CTS Automatic >> Repair and Diagnosis >> Engine Performance >> System >> Engine Controls - Self-Diagnostics >> Drive Cycles >> Inspection/Maintenance Complete System Set Procedure >> Diagnostic Procedures
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Diagnostic Procedures

  1. If I/M system check has been performed, go to next step. If I/M system check has not been performed, go to INSPECTION/MAINTENANCE SYSTEM CHECK .
  2. Ensure that the vehicle is within the Conditions for Running. Turn OFF all of the accessories (e.g., A/C, blower fan, etc.). Set the vehicle parking brake. Verify the transmission is in Park for A/T and Neutral for M/T. Start engine. Allow engine to idle for 2 minutes. When complete, go to next step.
    3. WARNING: Road test a vehicle under safe conditions and while obeying all traffic laws. Do not attempt any maneuvers that could jeopardize vehicle control. Failure to adhere to these precautions could lead to serious personal injury and vehicle damage.
  3. Test drive vehicle. Ensure vehicle is accelerated at part throttle to 55 MPH. Drive vehicle at 55 MPH for 16 minutes. Decelerate vehicle to zero MPH. Idle engine for 40 seconds while service brake is depressed and automatic transmission is in Drive or manual transmission is in Neutral with clutch pedal depressed. Repeat procedure 4 times.
  4. Ensure vehicle is accelerated at part throttle to 45-55 MPH. Drive vehicle at 45-55 MPH for 8 minutes. Decelerate vehicle to zero MPH. Idle engine for 40 seconds while service brake is depressed and automatic transmission is in Drive or manual transmission is in Neutral with clutch pedal depressed. Repeat procedure 4 times.
  5. Using scan tool, observe I/M system status display. If all I/M system status indicators updated to YES, go to next step. If any I/M system status indicator did not update to YES, repeat I/M System Set Procedure for indicated system.
  6. Using scan tool, observe emission related DTC portion of I/M system status display. If scan tool indicates any emission related DTCs, perform appropriate diagnostic test. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If scan tool does not indicate emission related DTCs, system is okay.
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