GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the BCM System Check performed?

--

Go to Step 2

Go to Diagnostic System Check - Body Control System in Body Control System

2

Was the Audible Warnings System Check performed?

--

Go to Step 3

Go to Diagnostic System Check - Audible Warnings

3

  1. Turn the ignition switch to the OFF position.
  2. Remove the key from the ignition.
  3. Using the scan tool, enter BCM Data List.
  4. Select Input 1.

Does the KEY IN IGNITION test display NO?

--

Go to Step 4

Go to Step 8

4

  1. Turn the ignition switch to the OFF position.
  2. Remove the key from the ignition.
  3. Move the headlamp switch to the OFF position.
  4. Using the scan tool, enter BCM Data List.
  5. Select Input 2.

Does the PARKLAMPS test display OFF?

--

Go to Step 5

Go to Step 9

5

Inspect the connections at the BCM.

Are the connections in need of repair?

--

Go to Step 6

Go to Step 7

6

Repair the connections as necessary.

Is the repair complete?

--

Go to Diagnostic System Check - Audible Warnings

--

7

Replace the BCM. Refer to BCM Replacement in Body Control System.

Is the repair complete?

--

Go to Diagnostic System Check - Audible Warnings

--

8

Locate and repair the short to ground in CKT 80 between the BCM connector C2 terminal B9 and the key in ignition alarm switch.

Is the repair complete?

--

Go to Diagnostic System Check - Audible Warnings

--

9

Are the park lamps ON with the switch OFF?

--

Go to Exterior Lights System Check in Lighting Systems

Go to Step 5