GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 1999 🢒 Chevy C Silverado - 2WD 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Courtesy Lamps Inoperative

Step

Action

Value(s)

Yes

No

1
  1. Turn the ignition to the ON position.
  2. Ensure the dome lamp override switch is in the OFF position.
  3. Connect a scan tool.
  4. Using the scan tool, test for any DTCs in the body control module (BCM).

Does the scan tool show any DTCs?

--

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

Go to Step 2

2

Using the scan tool, read the dome override switch status.

Does the scan tool show the switch status as OFF?

--

Go to Step 6

Go to Step 3

3
  1. Disconnect the headlamp and panel dimmer switch.
  2. Using the scan tool, read the dome override switch status.

Does the scan tool show the switch status as OFF?

--

Go to Step 4

Go to Step 5

4

Repalce the headlamp and panel dimmer switch. Refer to Headlamp Switch Replacement .

Is the repair complete?

--

System OK

--

5

Locate and repair the short to ground in CKT 328 (PPL).

If no short is found, replace the BCM. Refer to Body Control Module Replacement in Body Control Systems.

Is the repair complete?

--

System OK

--

6
  1. Open the drivers or the passenger door.
  2. Using the scan tool, read the driver door jamb switch or the door handle switch status.

Does the scan tool show the switch status as Active?

--

Go to Step 12

Go to Step 7

7
  1. Disconnect LH or the RH mini wedge (door jamb switch).
  2. Connect a fused jumper wire from terminal A to terminal D of the switch for Base models. Connect a fused jumper wire form terminal C to terminal D of the switch for Uplevel models.
  3. Using the scan tool, read the driver door jamb switch status.

Does the scan tool show the switch status as Active?

--

Go to Step 8

Go to Step 9

8

Replace the LH or the RH mini wedge (door jamb switch). Refer to Front Side Door Lock Actuator Replacement in Doors.

Is the repair complete?

--

System OK

--

9
  1. Connect a fused jumper wire from terminal A to ground for Base models. Connect a fused jumper wire from terminal C to ground for Uplevel models.
  2. Using the scan tool, read the driver door jamb switch status.

Does the scan tool show the switch status as Active?

--

Go to Step 10

Go to Step 11

10

Locate and repair the open in CKT 1850 (BLK)/CKT 2450 (BLK) for an open to ground.

Is the repair complete?

--

System OK

--

11

Locate and repair the open in CKT 126 (TAN) between the LH mini wedge and the body control module (BCM).

If no open is found, replace the BCM. Refer to Body Control Module Replacement in Body Control Systems.

Is the repair complete?

--

System OK

--

12
  1. Remove the courtesy lamp relay.
  2. Using J 35616 adaptor, connect a fused jumper wire from terminal 30 to terminal 87 of the relay socket.
  3. Open the drivers door.

Do the courtesy lamps light?

--

Go to Step 13

Go to Step 14

13

Replace the courtesy lamp relay.

Is the repair complete?

--

System OK

--

14
  1. Reinstall the courtesy lamp relay.
  2. Remove the inadvert power relay.
  3. Using J 35616 adaptor, connect a fused jumper wire from terminal 30 to terminal 87 of the relay socket.
  4. Open drivers door.

Do the courtesy lamps light?

--

Go to Step 15

Go to Step 16

15

Replace the inadvert power relay.

Is the repair complete?

--

System OK

--

16

Replace the body control module. Refer to Body Control Module Replacement in Body Control Systems.

Is the repair complete?

--

System OK

--