GM Service Manual Online
For 1990-2009 cars only

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Action

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Schematic Reference: Interior Lights Schematics

Connector End View Reference: Lighting Systems Connector End Views , Computer/Integrating Systems Connector End Views in Computer/Integrating Systems, or Power Door Systems Connector End Views in Doors

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Turn ON the ignition, with the engine OFF.
  2. Place the headlamp switch in the HEADLAMP position.

Do the headlamps operate properly?

Go to Step 3

Go to Headlamps Inoperative - Low Beams

3

  1. Turn ON the ignition, with the engine OFF.
  2. Cover the ambient light sensor.
  3. Open and Close all of the doors.
  4. Place the courtesy lamp switch in the ON position.

Do the courtesy lamps operate properly?

Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 4

4

Are the courtesy lamps only inoperative with the interior lamp switch?

Go to Step 9

Go to Step 5

5

Are the courtesy lamps only inoperative with the door(s)?

Go to Step 11

Go to Step 6

6

Is there only one inoperative lamp?

Go to Step 14

Go to Step 7

7

  1. With a scan tool, select from the Rear Integration Module (RIM) Special Functions Output Control, the Courtesy Lamp #1, #2 w/o dim.
  2. With the scan tool, command the Courtesy Lamp #1, #2 w/o dim ON.

Are only the front interior lamps inoperative?

Go to Step 21

Go to Step 8

8

Are only the rear interior lamps inoperative?

Go to Step 22

Go to Step 16

9

  1. Place the interior lamp switch in the ON position.
  2. With a scan tool, observe the Interior Lamp Switch parameter in the IPM Non-HVAC data list.

Does the scan tool display ON?

Go to Step 30

Go to Step 10

10

  1. Disconnect the headlamp switch.
  2. Connect a 3-amp fused jumper between the interior lamp switch on signal circuit and a good ground.
  3. With a scan tool, observe the Interior Lamp Switch parameter in the IPM Non-HVAC data list.

Does the scan tool display ON?

Go to Step 29

Go to Step 23

11

  1. Open all of the doors.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe all of the Door Jamb Switch parameters in each of the Door Module inputs data lists.

Does the scan tool display ON for all of the doors?

Go to Step 28

Go to Step  12

12

  1. Turn OFF the ignition.
  2. Disconnect the appropriate door lock actuator.
  3. Connect a 3-amp fused jumper between the door open switch signal circuit and a good ground.
  4. Turn ON the ignition, with the engine OFF.
  5. With a scan tool, observe the Door Jamb Switch parameter.

Does the scan tool indicate that the Door Jamb Switch parameter is ON?

Go to Step 13

Go to Step 24

13

  1. Connect a 3-amp fused jumper between the door open switch signal circuit and the ground circuit of the door lock actuator.
  2. With a scan tool, observe the Door Jamb Switch parameter.

Does the scan tool indicate that the Door Jamb Switch parameter is ON?

Go to Step 27

Go to Step 33

14

  1. Remove the inoperative courtesy lamp bulbs.
  2. Connect a test lamp between the supply voltage circuit of the inoperative courtesy lamp and a good ground.

Does the test lamp illuminate?

Go to Step 15

Go to Step 35

15

Connect a test lamp between the supply voltage circuit of the inoperative courtesy lamp and the ground circuit of the inoperative courtesy lamp.

Does the test lamp illuminate?

Go to Step 32

Go to Step 34

16

  1. With a scan tool, select from the Rear Integration Module (RIM) Special Functions Output Controls, the Interior Lamp Relay.
  2. With the scan tool, command the INT LP relay ON and OFF.

Do you hear a click when you command the INT LP relay ON and OFF?

Go to Step 19

Go to Step 17

17

  1. Turn OFF the ignition.
  2. Disconnect the INT LP relay.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the battery positive voltage circuit of the INT LP relay coil and a good ground.

Does the test lamp illuminate?

Go to Step 18

Go to Step 36

18

  1. Connect a test lamp between the battery positive voltage circuit of the INT LP relay coil and the control circuit of the INT LP relay.
  2. With a scan tool, command the INT LP relay ON.

Does the test lamp illuminate?

Go to Step 26

Go to Step 25

19

  1. Turn OFF the ignition.
  2. Disconnect the INT LP relay.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the battery positive voltage circuit of the INT LP switch and a good ground.

Does the test lamp illuminate?

Go to Step 20

Go to Step 37

20

  1. Connect a 10-amp fused jumper between the battery positive voltage circuit of the INT LP relay switch and the courtesy lamp supply voltage circuit.
  2. Operate the interior lamps.

Do the interior lamps operate properly?

Go to Step 26

Go to Step 35

21

Test for an open or high resistance in the front interior lamp control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 45

Go to Step 31

22

Test for an open or high resistance in the rear interior lamp control circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 45

Go to Step 31

23

Test the interior lamp switch on signal circuit for high resistance, open or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 45

Go to Step 30

24

Test the door open switch signal circuit for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 45

Go to Step 28

25

Test for an open or high resistance in the control circuit of the INT LP relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 45

Go to Step 31

26

Inspect for poor connections at the INT LP relay. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 45

Go to Step 38

27

Inspect for poor connections at the harness connector of the door lock actuator. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 45

Go to Step 39

28

Inspect for poor connections at the harness connector of the appropriate door module. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 45

Go to Step 40

29

Inspect for poor connections at the harness connector of the headlamp switch. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 45

Go to Step 41

30

Inspect for poor connections at the harness connector of the instrument panel module (IPM). Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 45

Go to Step 42

31

Inspect for poor connections at the harness connector of the RIM. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 45

Go to Step 43

32

Inspect for poor connections at the inoperative courtesy lamp bulb connector. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 45

Go to Step 44

33

Repair an open or high resistance in the ground circuit of the door lock actuator. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 45

--

34

Repair the high resistance or open in the ground circuit of the inoperative courtesy lamp. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 45

--

35

Repair the high resistance or open in the supply voltage circuit of the courtesy lamps. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 45

--

36

Repair the high resistance or open in the battery positive voltage circuit of the INT LP relay coil. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 45

--

37

Repair the open or high resistance in the battery positive voltage circuit of the INT LP relay switch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 45

--

38

Replace the INT LP relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the replacement?

Go to Step 45

--

39

Replace the door lock actuator. Refer to Front Side Door Latch Replacement and Rear Side Door Latch Replacement in Doors.

Did you complete the replacement?

Go to Step 45

--

40

Replace the appropriate door module. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 45

--

41

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Did you complete the replacement?

Go to Step 45

--

42

Replace the IPM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 45

--

43

Replace the RIM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 45

--

44

Replace the inoperative courtesy lamp bulb.

Did you complete the replacement?

Go to Step 45

--

45

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2