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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2004 🢒 CTS 🢒 Accessories 🢒 Cruise Control 🢒 Diagnostic System Check - Cruise Control

Diagnostic System Check - Cruise Control 2.6L, 3.2L and 3.6L

Test Description

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

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

    2.

  2. The presence of DTCs which begin with U indicates that 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 in Data Link Communications

2

  1. Turn ON the ignition, with the engine OFF.
  2. Attempt to establish communication with the following modules:
    3. • The engine control module (ECM)
    • The electronic brake control module (EBCM)

Does the scan tool communicate with the modules listed above?

Go to Step 3

Go to Data Link References in Data Link Communications

3

Important::  The engine may start during the following step. Turn the engine OFF as soon as you have observed the Crank power mode.

  1. With a scan tool, access the Class 2 Power Mode in the Diagnostic Circuit Check.
  2. Rotate the ignition switch through all positions while observing the System Power Mode parameter.

Does the System Power Mode parameter reading match the ignition switch position for all switch positions?

Go to Step 4

Go to Power Mode Mismatch in Body Control System

4

Select the DTCs function on the scan tool for the following modules:

    • The ECM
    • The EBCM

Does the scan tool display any DTCs for the modules listed above?

Go to Step 5

Go to Symptoms - Cruise Control

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 P0560, P0562, P0563, P0615, P0616, P0617, P0625, P0626, P1668, P2500, or P2501?

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

Go to Diagnostic Trouble Code (DTC) List

Diagnostic System Check - Cruise Control 5.7L

Test Description

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

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

    2.

  2. The presence of DTCs which begin with U indicates that 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 in Data Link Communications

2

  1. Turn ON the ignition, with the engine OFF.
  2. Attempt to establish communication with the following modules:
    3. • Powertrain control module (PCM)
    • Electronic brake control module (EBCM)

Does the scan tool communicate with the modules listed above?

Go to Step 3

Go to Data Link References in Data Link Communications

3

Important::  The engine may start during the following step. Turn the engine OFF as soon as you have observed the Crank power mode.

  1. With a scan tool, access the Class 2 Power Mode in the Diagnostic Circuit Check.
  2. Rotate the ignition switch through all positions while observing the System Power Mode parameter.

Does the System Power Mode parameter reading match the ignition switch position for all switch positions?

Go to Step 4

Go to Power Mode Mismatch in Body Control System

4

Select the DTCs function on the scan tool for the following modules:

    • PCM
    • EBCM

Does the scan tool display any DTCs for the modules listed above?

Go to Step 5

Go to Symptoms - Cruise Control

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 P0560, P0562, P0563, P0615, P0616, P0617, P0622, or P1637?

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

Go to Diagnostic Trouble Code (DTC) List