GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2006 🢒 GTO 🢒 Body 🢒 Wiring Systems 🢒 Diagnostic System Check - Skip Shift System

Test Description

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

  1. Lack of communication may be due to a partial malfunction of the class 2 serial data circuit or due to a total malfunction of the class 2 serial data circuit. The specified procedure will determine the particular condition.

    2.

  2. The presence of DTCs which begin with "U" indicate some other module is not communicating. The specified procedure will compile all the available information before tests are performed.

Step

Action

Yes

No

1

Install a scan tool.

Does the scan tool power up?

Go to Step 2

Go to Scan Tool Does Not Power Up

2

  1. Turn ON the ignition, with the engine OFF.
  2. Attempt to establish communication with the powertrain control module (PCM).

Does the scan tool communicate with the PCM?

Go to Step 3

Go to Diagnostic Trouble Code (DTC) List - Vehicle

3

Select the PCM display DTCs function on the scan tool.

Does the scan tool display any DTCs?

Go to Step 4

Go to Testing for Intermittent Conditions and Poor Connections

4

Does the scan tool display any DTCs which begin with a "U"?

Go to Diagnostic Trouble Code (DTC) List - Vehicle

Go to Step 5

5

Does the scan tool display DTC P1637?

Go to Diagnostic Trouble Code (DTC) List - Vehicle

Go to Step 6

6

Does the scan tool display any DTCs which begin with "P" other then P0801, P0803?

Go to Diagnostic Trouble Code (DTC) List - Vehicle

Go to Diagnostic Trouble Code (DTC) List - Vehicle