GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2000 🢒 Catera 🢒 Engine 🢒 Engine Controls - 3.0L (L81) 🢒 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 malfunction of the Keyword 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 Theft Deterrent Module (Immobilizer).

Does the scan tool communicate with the Theft Deterrent Module?

Go to Step 3

Go to Scan Tool Does Not Communicate with Keyword 82 Data Line in Data Link Communications

3

Select the Immobilizer DTCs function on the scan tool.

Does the scan tool display any DTCs?

Go to DTC List

Go to Symptoms