Retrieving Trouble Codes

Ensure ignition is off. Using an OBD-II compatible scan tool, connect it to 16-pin Data Link Connector (DLC), located under instrument panel, to right of steering column. See Fig 1.
Turn ignition on. Ensure Malfunction Indicator Light (MIL) on instrument cluster illuminates. Retrieve and record DTC and freeze frame data following scan tool manufacturer's instructions.
Once a DTC is obtained, determine probable cause and symptom. See DTC IDENTIFICATION table. For trouble shooting of DTCs, see DIAGNOSTIC TESTING .

Fig 1: Identifying OBD-II Data Link Connector (DLC)

Courtesy of GENERAL MOTORS CORP.

DTC IDENTIFICATION

DTC

⁽¹⁾ Probable Cause

⁽²⁾ Transmission Range (TR) Switch Circuit

Vehicle Speed Sensor (VSS) Circuit

Direct Clutch Solenoid Circuit

2nd Brake Solenoid Circuit

Shift Malfunction

⁽¹⁾	Check listed component for probable cause. Check wiring and connections of specified component.

⁽²⁾	May also be known as Park/Neutral Position (PNP) switch.