GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2003 🢒 DeVille 🢒 Body and Accessories 🢒 Cruise Control 🢒 Diagnostic System Check - Cruise Control

Test Description

The number below refers to the step number 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.

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 following Control Modules.
    3. • Powertrain Control Module (PCM)
    • Instrument Cluster (IPC)
    • Electronic Brake Control Module (EBCM)

Does the scan tool communicate with these modules?

Go to Step 3

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

3

Select the IPC display DTC function on the scan tool.

Does the scan tool display any DTCs?

Go to Diagnostic Trouble Code (DTC) List in Instrument Panel Gages and Console

Go to Step 4

4

Select the ABS/TCS display DTC function on the scan tool.

Does the scan tool display any DTCs?

Go to Diagnostic Trouble Code (DTC) List in Antilock Brake System

Go to Step 5

5

Select the PCM display DTC function on the scan tool.

Does the scan tool display any DTCs?

Go to Diagnostic Trouble Code (DTC) List in Engine Controls

Go to Symptoms - Cruise Control