GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 2000 🢒 LeSabre 🢒 Engine 🢒 Engine Cooling 🢒 Diagnostic System Check

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 PCM stores DTCs that are related to the engine cooling system. Diagnose PCM DTCs related to engine cooling first.

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 PCM.

Does the scan tool communicate with the PCM?

Go to Step 3

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

3

Select the PCM display DTCs function on the scan tool.

Does the scan tool display any DTCs?

Go to Powertrain On Board Diagnostic (OBD) System Check in Engine Controls

Go to Symptoms