Diagnostic Procedures
WARNING: This page is about a different car, the 2003 GMC Sonoma and 2003 Chevrolet S10 Pickup. However, it is still accessible from the selected car via links, so may be relevant.
- Did you perform the Inspection/Maintenance (I/M) System Check? If yes, go to next step. If no, go to INSPECTION/MAINTENANCE SYSTEM CHECK
.NOTE: Whenever ignition is turned on, ignition positive voltage is supplied to HO2S heaters. After verifying the enable criteria, turn ignition off for about 5 minutes to allow sensors to cool before continuing with test.
-
- Preprogram scan tool with vehicle information before turning ignition on.
- Ensure vehicle is within the Conditions For Running DTC.
- Set parking brake.
- Verify transmission is in Park (A/T) or Neutral (M/T).
- Turn off all of accessories (e.g., A/C, blower fan, etc.).
- Start and allow engine to idle.
- Operate engine at idle until I/M System Status indicator updates to YES.
If HO2S heater system status updates to YES within 2 minutes, go to step 5 . If HO2S heater system status does not update to YES within 2 minutes, go to next step.
- Using scan tool, observe DTC information. Does scan tool indicate any failed DTCs? If yes, diagnose affected DTCs. See DIAGNOSTIC TROUBLE CODE DEFINITIONS
. If no, go to next step.NOTE: Refer to INSPECTION/MAINTENANCE SYSTEM DTCS to determine which DTCs are required to run in order to complete this test.
- Using scan tool, observe the NOT RAN SINCE CODE CLEARED display. Determine which of the DTCs required for a YES status has not run. Enter the DTC number in the Specific DTC menu of scan tool. Operate vehicle within the Conditions For Running the DTC. See CONDITIONS FOR RUNNING DTC . Repeat the procedure until scan tool indicates the diagnostic test has run. Repeat this step for any additional required DTCs that have not run. Using scan tool, observe I/M System Status display. Did the HO2S Heater System Status update to YES? If yes, go to next step. If no, see DIAGNOSTIC AIDS .
- Using scan tool, observe emission related DTC portion of I/M System Status display. Does scan tool indicate any emission related DTCs set? If yes, diagnose affected DTCs. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no, system is okay.