GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2001 🢒 Impala 🢒 Transmission/Transaxle 🢒 Shift Lock Control 🢒 Diagnostic System Check - Automatic Transmission Shift Lock Control

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. Checks for Diagnostic Trouble Codes (DTCs) in the BCM and the PCM.

    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.

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 body control module (BCM) and the powertrain control module (PCM).

Does the scan tool communicate with the BCM?

Go to Step 3

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

3

Select the BCM and PCM display DTCs function on the scan tool.

Does the scan tool display any DTCs?

Go to Step 4

Go to Symptoms - Automatic Transmission Shift Lock Control

4

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 5

5

Does the scan tool display DTC B1000?

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

Go to Step 6

6

Does the scan tool display DTC P1819, 1820, 1822, 1823 or 1825?

Go to Diagnostic Trouble Code (DTC) List/Type in Automatic Transmissions

Go to Step 7

7

Does the scan tool display DTC B2712 or B3713?

Go to Diagnostic Trouble Code (DTC) List

Go to Symptoms - Automatic Transmission Shift Lock Control