LEMON Manuals: Even more car manuals for everyone
Home >> Oldsmobile >> 1998 >> Intrigue Base >> Repair and Diagnosis >> External Pages >> Different car >> Section 21 (Engine Control System - Tests W/Codes - Introduction) >> Self-Diagnostic System >> Hard Or Intermittent Trouble Code Determination

Hard Or Intermittent Trouble Code Determination

WARNING: This page does not describe the selected car, but rather 68 other vehicles, including the 1999 Saturn SW2, 1999 Saturn SW1, 1999 Saturn SL2, 1999 Saturn SL1, and 1999 Saturn SL. However, it is still accessible from the selected car via links, so may be relevant.

During any diagnostic procedure, determine if DTC(s) are hard failure codes or intermittent failure codes. Diagnostic procedures will not always help analyze intermittent codes. To determine hard codes and intermittent codes:

  1. Enter diagnostic mode. Read and record all stored DTCs. Exit diagnostic mode and clear DTCs. See CLEARING DIAGNOSTIC TROUBLE CODES (DTCS) .
  2. Apply parking brake and place transmission in Neutral or Park. Block drive wheels and start engine. MIL should turn off. Allow engine to reach normal operating temperature and continue to run for 2 minutes and note MIL.
  3. If MIL illuminates, enter diagnostic mode. Read and record DTCs. This will reveal hard failure codes. Oxygen sensor related DTCs may require a road test to reset hard failures after DTCs were cleared.
  4. If MIL does not illuminate, all stored DTCs were intermittent failures.

NOTE: DTCs will be recorded at various operating times. Some DTCs require operation of that sensor or switch for 5 seconds; others require operation for 5 minutes or longer at normal operating temperature, vehicle speed and load. Therefore, some DTCs may not set in a service bay operational mode and may require road testing vehicle in order to duplicate conditions under which code will set.
scientia non olet · About LEMON Manuals