Test Description

WARNING: This page is about a different car, the 2003 Pontiac Montana, 2003 Oldsmobile Silhouette, and 2003 Chevrolet Venture. However, it is still accessible from the selected car via links, so may be relevant.

The numbers below refer to the step numbers on the diagnostic table.

This step determines if the scan tool is receiving power through the DLC connector.
The MIL should illuminate whenever the ignition is ON and the engine is not running.
This step determines if the PCM is transmitting class 2 serial data to the DLC and that the Class 2 data circuit is not open or shorted.
This step determines if a DTC is current or stored in history.

Fig 1: Diagnostic System Check-Automatic Transmission (3.4L)
Courtesy of GENERAL MOTORS CORP.

Fig 2: Scan Tool Output Controls (1 of 3)
Courtesy of GENERAL MOTORS CORP.

Fig 3: Scan Tool Output Controls (2 of 3)
Courtesy of GENERAL MOTORS CORP.

Fig 4: Scan Tool Output Controls (3 of 3)
Courtesy of GENERAL MOTORS CORP.