GM Service Manual Online
For 1990-2009 cars only

Test Description

The number(s) below refer to the Step number(s) 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. The symptom list in Symptoms will determine the correct diagnostic procedure to use.

  3. The presence of DTCs which begin with U indicate some other module is not communicating.

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 in Data Link Communications.

2

  1. Turn ON the ignition, with the engine OFF.
  2. Attempt to establish communication with the tilt/telescoping steering column control module.

Does the scan tool communicate with the module?

Go to Step 4

Go to Step  3

3

Attempt to operate the tilt/telescoping steering column In/Out/Up/Down functions.

Does the column move?

Go to Scan Tool Does Not Communicate with Class 2 Device in Data Link Communications

Go to Steering Column Tilt/Telescoping Inoperative

4

Select the display DTCs function on the scan tool for the tilt/telescoping steering column control module

Does the scan tool display any DTCs?

Go to Step 5

Go to Symptoms

5

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

Go to Diagnostic Trouble Code (DTC) List in Data Link Communications

Go to Step 6

6

Does the scan tool display DTC B1007 or B1009?

Go to Diagnostic Trouble Code (DTC) List/Type in Body Control Systems

Go to Step 7

7

Does the scan tool display DTC B1327 or B1328?

Go to Diagnostic Trouble Code (DTC) List/Type in Engine Electrical -- 4.6L

Go to Diagnostic Trouble Code (DTC) List/Type