GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2001 🢒 Catera 🢒 Body and Accessories 🢒 Wiring Systems 🢒 Diagnostic System Check - Theft Deterrent

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.

  2. The symptoms list in Symptoms will determine the correct diagnostic procedure to use.

    3.

  3. 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.

    4.

  4. The presence of DTC P0601, P0602, P0603, P0604 or P0606 indicates an internal fault in the ECM.

  5. The presence of DTC B1552, B1656, B1558 or B1973 indicates an internal module fault.

    6.

  6. The Presence of DTC B1982 or B1983 indicates a low or high voltage condition.

Step

Action

Yes

No

Schematic Reference: Theft Deterrent System Schematics

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. • Engine Control Module (ECM)
    • Immobilizer
    • Instrument Panel Cluster (IPC)
    • Body Control Module (BCM)

Does the scan tool communicate with the all the listed control modules?

Go to Step 3

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

3

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

    • Engine Control Module (ECM)
    • Immobilizer
    • Instrument Panel Cluster (IPC)
    • Body Control Module (BCM)

Does the scan tool display any DTCs?

Go to Step 4

Go to Symptoms - Theft Deterrent

4

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

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

Go to Step 5

5

Does the scan tool display DTC P0601, P0602, P0603, P0604 or P0606?

Go to Diagnostic Trouble Code (DTC) List in Engine Controls - 3.0L (L81)

Go to Step 6

6

Does the scan tool display DTC B1552, B1556, B1558 or B1973?

Go to Diagnostic Trouble Code (DTC) List in Body Control System

Go to Step 7

7

Does the scan tool display DTC B1982 or B1983?

Go to DTC B1982 or DTC B1983 in Engine Electrical

Go to Diagnostic Trouble Code (DTC) List