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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2000 🢒 Seville 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Courtesy Lamps Inoperative

Courtesy Lamps Inoperative All

Step

Action

Value(s)

Yes

No

1

Did you perform the Lighting System Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2
  1. Turn the ignition switch to the ON position.
  2. Connect a scan tool to the data link connector (DLC).
  3. Select Open/Short Data from the instrument panel integration module (IPM) Data Display.
  4. Place the interior lamp switch in the AUTO position.

Does the scan tool indicate that the Interior Lamp Switch was in the Auto position?

--

Go to Step 3

Go to Step 15

3
  1. Place the interior lamp switch to the ON position.
  2. Backprobe the rear fuse block connector C2 with a DMM from battery positive voltage (B+) to cavity E11 (GRY).

Is the voltage within the specified range?

10-15 V

Go to Step 4

Go to Step 6

4

Backprobe the rear fuse block connector C2 with a DMM from cavity E12 (DK BLU/WHT) to ground.

Is the voltage within the specified range?

10-15 V

Go to Step 5

Go to Step 8

5

Repair the open in CKT 149 (DK BLU/WHT). Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Step 20

--

6
  1. Remove the INT LP relay from the rear fuse block.
  2. Disconnect the rear integration module (RIM) connector C1.
  3. Backprobe with a DMM from the rear fuse block connector C2 cavity E11 (GRY) to the RIM connector C1 cavity B4 (GRY).

Is the resistance less than the specified value?

5 ohms

Go to Step 7

Go to Step 12

7

Replace the rear integration module (RIM). Refer to Rear Integration Body Control Module Replacement in Body Control System.

Is the RIM replacement complete?

--

Go to Step 20

--

8

Check the rear fuse block INT LP Fuse for an open.

Is the INT LP Fuse OK?

--

Go to Step 9

Go to Step 10

9

Replace the INT LP Relay in the rear fuse block.

Do the courtesy lamps now operate properly?

--

Go to Step 20

Go to Step 11

10
  1. Remove the INT LP relay from the rear fuse block.
  2. Backprobe with a DMM from the rear fuse block connector C2 cavity E12 (DK BLU/WHT) to ground.

Is the resistance less than the specified value?

5 ohms

Go to Step 13

Go to Step 11

11
  1. Check for proper terminal contact at the rear fuse block connector C2 cavities E11 (GRY) and E12 (DK BLU/WHT). Refer to Wiring Repairs in Wiring Systems.
  2. If OK, replace the rear fuse block. Refer to Rear Electrical Center or Junction Block Replacement in Wiring Systems.

Is the rear fuse block replacement complete?

--

Go to Step 20

--

12

Repair the open in CKT 1599 (GRY) between the rear fuse block and the RIM. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Step 20

--

13

Repair the short to ground in CKT 149 (DK BLU/WHT). Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Step 13

--

14

Replace the INT LP Fuse in the rear fuse block.

Is the fuse replacement complete?

--

Go to Step 20

--

15

Disconnect the overhead console connector C1.

Does the scan tool indicate that the Interior Lamp Switch was in the Off position?

--

Go to Step 16

Go to Step 18

16

Disconnect the instrument panel integration module (IPM) connector C1.

Does the scan tool indicate that the Interior Lamp Switch was in the Off position?

--

Go to Step 17

Go to Step 19

17

Replace the instrument panel integration module (IPM). Refer to Instrument Panel Module Replacement in Body Control System.

Is the IPM replacement complete?

--

Go to Step 20

--

18

Replace the overhead console. Refer to Roof Console Replacement in Interior Trim.

Is the overhead console replacement complete?

--

Go to Step 20

--

19

Repair the short to ground in CKT 1598 (GRY/BLK). Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Step 20

--

20

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK

Go to Step 2

Courtesy Lamps Inoperative Front

Step

Action

Value(s)

Yes

No

1

Did you perform the Lighting System Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2

Are all lamps controlled by the FRT CTSY Relay inoperative?

--

Go to Step 4

Go to Step 3

3

Are only the RH front door, RH rear door, and RH foot well courtesy lamps inoperative?

--

Go to Step 9

Go to Step 10

4
  1. Cover the ambient light sensor.
  2. Open a rear door.

Do the rear reading lamps light?

--

Go to Step 5

Go to Courtesy Lamps Inoperative

5
  1. Close all doors.
  2. Turn the ignition switch to the ON position.
  3. Connect a scan tool to the data link connector (DLC).
  4. Select Outputs from the rear integration module (RIM) Special Functions.
  5. Command the Front Courtesy Relay to be ON.

Do the courtesy lamps controlled by the FRT CTSY Relay light?

--

Go to Step 14

Go to Step 6

6

Backprobe with a DMM from battery positive voltage (B+) to the rear fuse block connector C2 cavity A12 (DK BLU).

Is the voltage within the specified range?

10-15 V

Go to Step 7

Go to Step 11

7

Replace the FRT CTSY Relay in the rear fuse block.

Do the courtesy lamps controlled by the FRT CTSY Relay light?

--

Go to Step 14

Go to Step 8

8
  1. Check for proper terminal contact at the rear fuse block connector C2 cavities A12 (DK BLU) and B12 (GRY). Refer to Wiring Repairs in Wiring Systems.
  2. If OK, replace the rear fuse block. Refer to Rear Electrical Center or Junction Block Replacement in Wiring Systems.

Is the rear fuse block replacement complete?

--

Go to Step 14

--

9

Repair the open in CKT 157 (GRY) between the rear fuse block and C308. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Step 14

--

10

Repair the open in CKT 157 (GRY) between the rear fuse block and C301. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Step 14

--

11
  1. Disconnect the rear integration module (RIM) connector C2.
  2. Backprobe with a DMM from the rear fuse block connector C2 cavity A12 (DK BLU) to the RIM connector C2 cavity A2 (DK BLU).

Is the resistance less than the specified value?

5 ohms

Go to Step 12

Go to Step 13

12

Replace the rear integration module (RIM). Refer to Rear Integration Body Control Module Replacement in Body Control System.

Is the RIM replacement complete?

--

Go to Step 14

--

13

Repair the open in CKT 1393 (DK BLU) between the rear fuse block and the RIM. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Step 14

--

14

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK.

Go to Step 2

Courtesy Lamps Inoperative Rear

Step

Action

Value(s)

Yes

No

1

Did you perform the Lighting System Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

2
  1. Cover the ambient light sensor.
  2. Open a rear door.

Do the courtesy lamps controlled by the FRT CTSY Relay light?

--

Go to Step 3

Go to Courtesy Lamps Inoperative

3
  1. Close all doors.
  2. Turn the ignition switch to the ON position.
  3. Connect a scan tool to the data link connector (DLC).
  4. Select Outputs from the rear integration module (RIM) Special Functions.
  5. Command the Rear Courtesy Relay to be ON.

Do the courtesy lamps controlled by the RR CTSY Relay light?

--

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

Go to Step 4

4

Backprobe with a DMM from battery positive voltage (B+) to the rear fuse block connector C3 cavity F11 (DK BLU/WHT).

Is the voltage within the specified range?

10-15 V

Go to Step 5

Go to Step 8

5

Backprobe with a DMM from battery positive voltage (B+) to the rear fuse block connector C3 cavity F10 (GRY/BLK).

Is the voltage within the specified range?

10-15 V

Go to Step 11

Go to Step 6

6

Replace the RR CTSY Relay in the rear fuse block.

Do the courtesy lamps controlled by the RR CTSY Relay light?

--

Go to Step 12

Go to Step 7

7
  1. Check for proper terminal contact at the rear fuse block connector C3 cavities F10 (GRY/BLK) and F11 (DK BLU/WHT). Refer to Wiring Repairs in Wiring Systems.
  2. If OK, replace the rear fuse block.

Is the rear fuse block replacement complete?

--

Go to Step 12

--

8
  1. Disconnect the rear integration module (RIM) connector C2.
  2. Backprobe with a DMM from the rear fuse block connector C3 cavity F10 (GRY/BLK) to the RIM connector C2 cavity A1 (GRY/BLK).

Is the resistance less than the specified value?

5 ohms

Go to Step 9

Go to Step 10

9

Replace the rear integration module (RIM). Refer to Rear Integration Body Control Module Replacement in Body Control System.

Is the RIM replacement complete?

--

Go to Step 12

--

10

Repair the open in CKT 690 (GRY/BLK) between the rear fuse block and the RIM. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Step 12

--

11

Repair the open in CKT 1495 (DK BLU/WHT) between the rear fuse block and C305. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Step 12

--

12

Operate the system in order to verify the repair.

Did you correct the condition?

--

System OK.

Go to Step 2