Diagnostic Procedures
- Perform powertrain diagnostic system check. See POWERTRAIN DIAGNOSTIC SYSTEM CHECK under SELF-DIAGNOSTIC SYSTEM. After performing diagnostic system check, go to next step.
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- Operate engine at idle until engine reaches operating temperature of at least 158°F (70°C). This may take up to 8-10 minutes, depending on start-up coolant temperature.
- Accelerate vehicle at part throttle to 30-40 MPH.
- Maintain this speed without changing throttle position for 3 minutes.
- Using scan tool, observe DTC Information. If scan tool indicates any failed DTCs, diagnose affected DTCs. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no DTCs are set, go to next step.
- Using scan tool, observe the NOT RAN SINCE CODE CLEARED display. Determine which of the DTCs required for a YES status has not run. Operate vehicle within Conditions For Running DTC. Monitor status of DTCs that are necessary to complete the test in the NOT RAN SINCE CODE CLEARED display of scan tool. Repeat this procedure until scan tool indicates that 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. If EGR System Status updates to YES, go to next step. If status does not update to YES, go to DIAGNOSTIC AIDS .
- Using scan tool, observe the emission related DTC portion of I/M System Status display. If scan tool indicates any emission related DTCs set, diagnose affected DTCs. See DIAGNOSTIC TROUBLE CODE DEFINITIONS . If no DTCs are displayed, system is okay.
CAUTION:
Road test a vehicle under safe conditions and while obeying all traffic laws. DO NOT attempt any maneuvers that could jeopardize vehicle control and could result in serious personal injury and vehicle damage.
NOTE:
Refer to INSPECTION/MAINTENANCE SYSTEM DTC TABLE
to determine which DTCs are required to run in order to complete this test.