GM Service Manual Online
For 1990-2009 cars only

Diagnostic Instructions

    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

System

DTCs Required to Set System Status to YES

If an I/M System Status indicator did NOT update to YES during the Inspection/Maintenance (I/M) Complete System Set ProcedureReview each indicator and reference this table to determine each DTC associated with the I/M System Status Indicator. Each DTC listed below has specific conditions that must be met for the diagnostic to run. Included within the conditions are additional DTCs which, if set, may inhibit the DTCs listed below from running. Reviewing and operating the vehicle within the Conditions for Running for each DTC listed below will allow the I/M System Status Indicators to transition to YES.

AIR

DTC P0411, P0412, P0418, P2440, or P2444

Catalyst

DTC P0420

EGR

DTC P0401

DTC P0403, P0404, P0405, P0406, or P042E

EVAP

DTC P0442

DTC P0446

DTC P0455

DTC P0496

Oxygen Sensor

DTC P0030, P0036, P0053, P0054, P0135, or P0141

DTC P0050, P0059, or P0155

DTC P0131, P0132, P0137, or P0138

DTC P0133, P0134, P0140, P1133, P2270, P2271, P2A00, or P2A01

DTC P0151 or P0152

DTC P0153, P0154, P1153, or P2A03