GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

Important:

    • Inspect the condition of the body control module (BCM), Ign 1, the cruise and the park lamp fuses (located in the left bussed electrical center (LBEC) and the mid bussed electrical center MBEC). If any fuse is open, replace the fuse and retest system for intermittent fuse failure. If the fuse continues to fail locate and repair source of overload. Refer to Power Distribution Schematics.
    • Inspect to make sure that Ground G203 and G304 are clean and tight.
    • This diagnostic table assumes that all other chimes function properly.

1

  1. Turn ON the ignition.
  2. Using a scan tool, read the BCM input data for key in ignition.

Does the scan tool read the specific value?

YES

Go to Step 2

Go to Step 4

2

  1. Open the driver door.
  2. Using a scan tool, read the BCM input data for the driver door jamb switch.

Does the scan tool read the specific value?

ACTIVE

Go to Step 3

Go to Step 9

3

Replace the BCM. Refer to Body Control Module Replacement in Body Control Systems.

Is the repair complete?

--

System OK

--

4

  1. Turn OFF the ignition.
  2. Leave the drivers door open.
  3. Disconnect the in-line connector C201B at the steering column.
  4. Connect a fused jumper between CKT 80 (LT GRN) cavity B3 and CKT 1850 (BLK) cavity B4.

Does the key in ignition data read the specific value?

YES

Go to Step 5

Go to Step 6

5

Replace the key in the ignition switch.

Is the repair complete?

--

System OK

--

6

Connect a self powered test lamp between CKT 1850 (BLK) cavity B4 and ground.

Does the test lamp light?

--

Go to Step 8

Go to Step 7

7

Locate and repair the open in CKT 1850 (BLK) between C201B and ground.

Is the repair complete?

--

System OK

--

8

Locate and repair the open in CKT 80 (LT GRN) between C201B and the BCM.

Is the repair complete?

--

System OK

--

9

  1. Turn OFF the ignition.
  2. Remove the connector combs from the BCM connector C3, leaving the BCM connected.
  3. Using the appropriate probe from the J 35616 connector test adapter kit, backprobe CKT 126 (TAN) cavity B4 to ground with a fused jumper.
  4. Turn ONthe ignition.

Does the driver door jamb switch read the specified data?

--

Go to Step 11

Go to Step 10

10

Replace the BCM.

Is the repair complete?

--

System OK

--

11

  1. Disconnect drivers door jamb switch connector.
  2. Connect a fused jumper between the drivers door jamb switch CKT 126 (TAN) cavity A (base truck) or cavity C (up level truck) and CKT 1850 (BLK) cavity D.

Does the driver door jamb switch read specific data?

--

Go to Step 12

Go to Step 13

12

Replace the drivers door jamb switch.

Is the repair complete?

--

System OK

--

13

Connect a self powered test lamp between CKT 1850 (BLK) cavity D and ground.

Does the test lamp light?

--

Go to Step 14

Go to Step 15

14

Locate and repair the open in CKT 126 (TAN) between the drivers door jamb switch and the BCM.

Is the repair complete?

--

System OK

--

15

Locate and repair the open in CKT 1850 (BLK) between the drivers door jamb switch and ground.

Is the repair complete?

--

System OK

--

16

Locate and repair as needed.

Is the repair complete?

--

System OK

--