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For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2000 🢒 Tahoe Limited 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Courtesy or Dome Lamps Inoperative

Courtesy or Dome Lamps Inoperative Except Luxury

Step

Action

Value(s)

Yes

No

1

Did you perform the Interior Lamps System Check?

--

Go to Step 2

Go to Interior Lamps System Check

2

Move the courtesy lamp switch to the ON position.

Do all of the lamps light?

--

Go to Step 4

Go to Step 3

3

Do some of the lamps light?

--

Go to Step 14

Go to Step 6

4
  1. Move the courtesy lamp switch to the OFF position.
  2. Move the dome lamp defeat switch to the OFF position.
  3. While opening and closing each door, observe the lamps.

Do all of the lamps light when each door is open?

--

Go to Interior Lamps System Check

Go to Step 5

5

Are the lamps inoperative only when certain doors are open?

--

Go to Step 15

Go to Step 8

6

Using a test lamp, backprobe the front dome lamp connector from CKT 40 (ORN) to ground.

Does the test lamp light?

--

Go to Step 7

Go to Step 16

7

Using a test lamp, backprobe the headlamp and panel dimmer switch connector from cavity M to ground.

Does the test lamp light?

--

Go to Step 17

Go to Step 18

8
  1. Open the door.
  2. Ensure that the dome defeat switch is in the OFF position.
  3. Disconnect the interior lamp control module connector.
  4. Connect a self-powered test lamp from the interior lamp control module connector, cavity B, to ground.

Does the test lamp light?

--

Go to Step 11

Go to Step 9

9
  1. Disconnect the headlamp and panel dimmer switch connector.
  2. Connect a self-powered test lamp from the headlamp and panel dimmer switch, cavity B, to the interior lamp control module connector, cavity B.

Does the test lamp light?

--

Go to Step 10

Go to Step 19

10
  1. Reconnect the headlamp and panel dimmer switch connector.
  2. Using a self-powered test lamp, backprobe from cavity B to cavity L.

Does the test lamp light?

--

Go to Step 20

Go to Step 21

11

With the interior lamp control module connector disconnected, connect a test lamp from cavity E to ground.

Does the test lamp light?

--

Go to Step 12

Go to Step 22

12

Connect a test lamp between the interior lamp control module, cavity C, and ground.

Does the test lamp light?

--

Go to Step 13

Go to Step 23

13

Connect a self-powered test lamp between the interior lamp control module, cavity D, and ground.

Does the test lamp light?

--

Go to Step 24

Go to Step 25

14
  1. Inspect for an open in the appropriate circuit:
    2. • CKT 40 (ORN) between the splice and the affected lamp
    • CKT 156 (WHT) between the splice and the affected lamp
    • CKT 150 (BLK) between the affected lamp and ground G400
  2. Repair the circuit, as necessary.

Did you find and correct a condition?

--

Go to Interior Lamps System Check

Go to Step 26

15
  1. Inspect for an open in CKT 328 (PPL) between the splice and the affected door jamb switch.
  2. Repair the circuit, as necessary.

Did you find and correct a condition?

--

Go to Interior Lamps System Check

Go to Step 27

16

Repair the open in CKT 40 (ORN) between splice S242 and the instrument panel fuse block.

Is the repair complete?

--

Go to Interior Lamps System Check

--

17

Repair the open in CKT 156 (WHT) between the headlamp and panel dimmer switch and splice S209.

Is the repair complete?

--

Go to Interior Lamps System Check

--

18
  1. Inspect for an open in CKT 150 (BLK) between the headlamp and panel dimmer switch and ground G200.
  2. Repair the circuit, necessary.

Did you find and correct the condition?

--

Go to Interior Lamps System Check

Go to Step 21

19

Repair the open in CKT 157 (GRY) between the headlamp and panel dimmer switch and the interior lamp control module.

Is the repair complete?

--

Go to Interior Lamps System Check

--

20

Repair the open in CKT 150 (BLK) between the headlamp and panel dimmer switch and ground G200.

Is the repair complete?

--

Go to Interior Lamps System Check

--

21

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

Is the repair complete?

--

Go to Interior Lamps System Check

--

22

Repair the open in CKT 156 (BLK) between the interior lamp control module and splice S246.

Is the repair complete?

--

Go to Interior Lamps System Check

--

23

Repair the open in CKT 40 (ORN) between the interior lamp control module and splice S248.

Is the repair complete?

--

Go to Interior Lamps System Check

--

24

Replace the interior lamp control module.

Is the repair complete?

--

Go to Interior Lamps System Check

--

25

Repair the open in CKT 150 (BLK) between the interior lamp control module and ground G202.

Is the repair complete?

--

Go to Interior Lamps System Check

--

26

Replace the affected lamp. Refer to Door Courtesy Lamp and Reflector Replacement .

Is the repair complete?

--

Go to Interior Lamps System Check

--

27

Replace the affected door jamb switch. Refer to Door Jamb Switch Replacement .

Is the repair complete?

--

Go to Interior Lamps System Check

--

Courtesy or Dome Lamps Inoperative Luxury

Step

Action

Value(s)

Yes

No

DEFINITION: This diagnostic chart should be used if some or all of the courtesy/dome lamps are inoperative with the courtesy lamp switch.

1
  1. Move dome lamp defeat switch to OFF position.
  2. Move the courtesy lamp switch to the ON position

Do some of the lamps light?

--

Go to Step  2

Go to Step 7

2
  1. Go to suspect courtesy/dome lamp.
  2. Connect a test lamp between cavity A, of suspect connector and ground.

Does test lamp light?

--

Go to Step 3

Go to Step 5

3

Connect a DMM, set on Ohms, between cavity B of suspect connector and ground.

Is continuity present?

--

Go to Step 4

Go to Step 6

4

Replace suspect bulb or lamp socket. Refer to Door Courtesy Lamp and Reflector Replacement .

Is the repair complete?

--

System OK

--

5

Locate and repair open in CKT 40 (ORN) between suspect connector and the body control module.

Is the repair complete?

--

System OK

--

6
  1. Disconnect headlamp and panel dimmer switch.
  2. Connect a DMM, set on Ohms, between suspect connector cavity B and the headlamp and panel dimmer switch connector cavity M.

Is continuity present?

--

Go to Step 7

Go to Step 11

7

Was the BCM Diagnostic System Check performed?

--

Go to Step 8

Go to DTC 12 Diagnostic System Check

8

Connect a test lamp between connector C305 cavity C8 and ground.

Does test lamp light?

--

Go to Step 10

Go to Step 9

9

Check for an open in CKT 40 (ORN) between connector C305 and splice S248, repair as necessary.

Did you find and repair an open circuit?

--

System OK

Go to Step 11

10
  1. Check for an open in CKT 40 (ORN) between connector C305 and the body control module, repair as necessary.
  2. If no open was found, replace the BCM.

Is the repair completed?

--

System OK

--

11
  1. Disconnect the headlamp and panel dimmer switch.
  2. Connect a DMM, set on Ohms, between headlamp and panel dimmer switch terminal R, and ground.

Is continuity present?

--

Go to Step  12

Go to Step 15

12

Connect a DMM, set on Ohms, between headlamp and panel dimmer switch terminals M and R.

Is continuity present?

--

Go to Step 14

Go to Step 13

13

Replace headlamp and panel dimmer switch. Refer to Headlamp Switch Replacement .

Is the repair complete?

--

System OK

--

14

Locate and repair open in CKT 156 (WHT) between suspect connector and headlamp and panel dimmer switch.

Is the repair complete?

--

System OK

--

15

Locate and repair open in CKT 150 (BLK) between headlamp and panel dimmer switch and ground G200.

Is the repair complete?

--

System OK

--