Diagnostic Procedure
WARNING: This page is about a different car, the 2002 Chevrolet Cavalier. However, it is still accessible from the selected car via links, so may be relevant.
- If inspection/maintenance system check has been performed, go to next step. If inspection/maintenance system check has not been performed, go to INSPECTION/MAINTENANCE SYSTEM CHECK . After performing inspection/maintenance system check, go to next step.
- Ensure vehicle is within CONDITIONS FOR RUNNING . Turn off all accessories. Start engine and allow to idle. Road test vehicle. For this test to run, accelerate at part throttle to 45-55 MPH. Maintain this speed for 6 minutes or until I/M System Status updates to YES. Vehicles equipped with M/T (5 or 6 speed) may require operation in 4th or 5th gear respectively, for this test to run. Using scan tool, review I/M System Status display. Did the HO2S/O2S System Status update to YES? If yes, go to step 5 . If no, go to next step.
- Using scan tool, monitor DTC Information for both AF ECM and PCM. If scan tool indicates any failed DTC, go to DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM. If scan tool does not indicate any failed DTCs, go to next step.
- Using scan tool, monitor NOT RAN SINCE CODE CLEARED display. Determine which HO2S/O2S DTCs required for a YES status, have not run. Enter DTC number in SPECIFIC DTC menu of scan tool. Operate vehicle within CONDITIONS FOR RUNNING . Repeat until scan tool indicates diagnostic test has run. Repeat for any additional required DTCs that have not run. Using scan tool, observe I/M System Status display. If HO2S/O2S System Status updates to YES, go to next step. If HO2S/O2S System Status does not update to YES, go to DIAGNOSTIC AIDS .
- Using scan tool, monitor Emission Related DTC portion of I/M System Status display. Does scan tool indicate any emission related DTCs? If yes, go to DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS under SELF-DIAGNOSTIC SYSTEM. If no, system is okay.