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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1999 🢒 Catera 🢒 Body and Accessories 🢒 Lighting Systems 🢒 Courtesy Lamps Inoperative

Courtesy Lamps Inoperative Front Side Door Lamps Inop

Step

Action

Value(s)

Yes

No

DEFINITION: LH or RH front side door courtesy lamp is inoperative.

1

Did you perform the Interior Lights System Check?

--

Go to Step 2

Go to Interior Lamps System Check

2
  1. Turn the ignition to the ON position.
  2. Determine which front side door courtesy lamp is inoperative.

Is the LH front side door courtesy lamp inoperative?

--

Go to Step 8

Go to Step 3

3
  1. Disconnect the RH front side door courtesy lamp connector.
  2. Turn the ignition switch to the ON position.
  3. Turn the headlamp switch to the INTERIOR LAMPS ON position.
  4. Use the DMM to measure the voltage between terminal C2 of the RH front side door courtesy lamp connector and a known good ground.

Is the measured voltage within the specified value?

B+

Go to Step 5

Go to Step 4

4
  1. Locate an open or a high resistance in circuit AP806.
  2. Repair the open or the high resistance in circuit AP806.

Is the repair complete?

--

Go to Step 13

--

5

Use the DMM to measure the resistance between terminal C1 of the RH front side door courtesy lamp connector and a known good ground.

Is the measured resistance less than the specified value?

5 ohms

Go to Step 7

Go to Step 6

6
  1. Locate an open or a high resistance in circuits XP810 and/or XP809.
  2. Repair the open or the high resistance in circuits XP810 and/or XP809.

Is the repair complete?

--

Go to Step 13

--

7

Replace the RH front side door courtesy lamp. Refer to Door Lamp Replacement in Lighting Systems.

Is the replacement complete?

--

Go to Step 13

--

8
  1. Disconnect the LH front side door courtesy lamp connector.
  2. Turn the ignition switch to the ON position.
  3. turn the headlamp switch to the INTERIOR LAMPS ON position.
  4. Use the DMM to measure the voltage between terminal C2 of the LH front side door courtesy lamp connector and a known good ground.

Is the measured voltage within the specified value?

B+

Go to Step 10

Go to Step 9

9
  1. Locate an open or a high resistance in circuit AP806.
  2. Repair the open or the high resistance in circuit AP806.

Is the repair complete?

--

Go to Step 13

--

10

Use the DMM to measure the resistance between terminal C1 of the LH front side door courtesy lamp connector and a known good ground.

Is the measured resistance less than the specified value?

5 ohms

Go to Step 12

Go to Step 11

11
  1. Locate an open or a high resistance in circuit XP810.
  2. Repair the open or the high resistance in circuit XP810.

Is the repair complete?

--

Go to Step 13

--

12

Replace the LH front side door courtesy lamp. Refer to Door Lamp Replacement in Lighting Systems.

Is the replacement complete?

--

Go to Step 13

--

13
  1. Connect all connectors and components that were disconnected.
  2. Verify that the LH and RH front side door courtesy lamps operate properly.

Do the LH and RH front side door courtesy lamps operate properly?

--

Go to Interior Lamps System Check

Go to Step 1

Courtesy Lamps Inoperative Rear Side Door Lamps Inop

Step

Action

Value(s)

Yes

No

DEFINITION: LH or RH rear side door courtesy lamp is inoperative.

1

Did you perform the Interior Lights System Check?

--

Go to Step 2

Go to Interior Lamps System Check

2
  1. Turn the ignition to the ON position.
  2. Determine which rear side door courtesy lamp is inoperative.

Is the LH rear side door courtesy lamp inoperative?

--

Go to Step 8

Go to Step 3

3
  1. Disconnect the RH rear side door courtesy lamp connector.
  2. Turn the ignition switch to the ON position.
  3. Use the DMM to measure the voltage between terminal C2 of the RH rear side door courtesy lamp connector and a known good ground.

Is the measured voltage within the specified value?

B+

Go to Step 5

Go to Step 4

4
  1. Locate an open or a high resistance in circuits AP804 and/or AP805.
  2. Repair the open or the high resistance in circuits AP804 and/or AP805.

Is the repair complete?

--

Go to Step 13

--

5
  1. Open the RH rear side door.
  2. Use the DMM to measure the resistance between terminal C1 of the RH rear side door courtesy lamp connector and a known good ground.

Is the measured resistance less than the specified value?

5 ohms

Go to Step 7

Go to Step 6

6
  1. Locate an open or a high resistance in circuits R1, R18 and/or R2.
  2. Repair the open or the high resistance in circuits R1, R18 and/or R2.
  3. If these circuits are OK, replace the RH rear side door jamb switch. Refer to Door Jamb Switch Replacement in Doors.

Is the repair or replacement complete?

--

Go to Step 13

--

7

Replace the RH rear side door courtesy lamp. Refer to Door Lamp Replacement in Lighting Systems.

Is the replacement complete?

--

Go to Step 13

--

8
  1. Disconnect the LH rear side door courtesy lamp connector.
  2. Turn the ignition switch to the ON position.
  3. Use the DMM to measure the voltage between terminal C2 of the LH rear side door courtesy lamp connector and a known good ground.

Is the measured voltage within the specified value?

B+

Go to Step 10

Go to Step 9

9
  1. Locate an open or a high resistance in circuit AP805.
  2. Repair the open or the high resistance in circuit AP805.

Is the repair complete?

--

Go to Step 13

--

10
  1. Open the LH rear side door.
  2. Use the DMM to measure the resistance between terminal C1 of the LH rear side door courtesy lamp connector and a known good ground.

Is the measured resistance less than the specified value?

5 ohms

Go to Step 12

Go to Step 11

11
  1. Locate an open or a high resistance in circuits R1, R17 and/or R2.
  2. Repair the open or the high resistance in circuits R1, R17 and/or R2.
  3. If these circuits are OK, replace the LH rear side door jamb switch. Refer to Door Jamb Switch Replacement in Doors.

Is the repair complete?

--

Go to Step 13

--

12

Replace the LH rear side door courtesy lamp. Refer to Door Lamp Replacement in Lighting Systems.

Is the replacement complete?

--

Go to Step 13

--

13
  1. Connect all connectors and components that were disconnected.
  2. Verify that the LH and RH rear side door courtesy lamps operate properly.

Do the LH and RH rear side door courtesy lamps operate properly?

--

Go to Interior Lamps System Check

Go to Step 1

Courtesy Lamps Inoperative Roof Rail Courtesy Lamps Inop

Step

Action

Value(s)

Yes

No

DEFINITION: LH or RH roof rail courtesy lamp is inoperative.

1

Did you perform the Interior Lights System Check?

--

Go to Step 2

Go to Interior Lamps System Check

2
  1. Turn the ignition to the ON position.
  2. Determine which roof rail courtesy lamp is inoperative.

Is the LH roof rail courtesy lamp inoperative?

--

Go to Step 10

Go to Step 3

3
  1. Disconnect the RH roof rail courtesy lamp connector.
  2. Turn the ignition switch to the ON position.
  3. Use the DMM to measure the voltage between terminal 1 of the RH roof rail courtesy lamp connector and a known good ground.

Is the measured voltage within the specified value?

B+

Go to Step 5

Go to Step 4

4
  1. Locate an open or a high resistance in circuits AP1 and/or AP809.
  2. Repair the open or the high resistance in circuits AP1 and/or AP809.

Is the repair complete?

--

Go to Step 17

--

5
  1. Turn the headlamp switch to the INTERIOR LAMPS ON position.
  2. Use the DMM to measure the resistance between terminal 3 of the RH roof rail courtesy lamp connector and a known good ground.

Is the measured resistance less than the specified value?

5 ohms

Go to Step 7

Go to Step 6

6
  1. Locate an open or a high resistance in circuits XP1 and/or XP805.
  2. Repair the open or the high resistance in circuits XP1 and/or XP805.

Is the repair complete?

--

Go to Step 17

--

7

Use the DMM to measure the resistance between terminal 2 of the RH roof rail courtesy lamp connector and a known good ground.

Is the measured resistance less than the specified value?

5 ohms

Go to Step 9

Go to Step 8

8
  1. Locate an open or a high resistance in circuits F1 and/or F88.
  2. Repair the open or the high resistance in circuits F1 and/or F88.

Is the repair complete?

--

Go to Step 17

--

9

Replace the RH roof rail courtesy lamp. Refer to Roof Side Rail Lamp Replacement in Lighting Systems.

Is the replacement complete?

--

Go to Step 17

--

10
  1. Disconnect the LH roof rail courtesy lamp connector.
  2. Turn the ignition switch to the ON position.
  3. Use the DMM to measure the voltage between terminal 1 of the LH roof rail courtesy lamp connector and a known good ground.

Is the measured voltage within the specified value?

B+

Go to Step 12

Go to Step 11

11
  1. Locate an open or a high resistance in circuits AP1 and/or AP810.
  2. Repair the open or the high resistance in circuits AP1 and/or AP810.

Is the repair complete?

--

Go to Step 17

--

12
  1. Turn the headlamp switch to the INTERIOR LAMPS ON position.
  2. Use the DMM to measure the resistance between terminal 3 of the LH roof rail courtesy lamp connector and a known good ground.

Is the measured resistance less than the specified value?

5 ohms

Go to Step 14

Go to Step 13

13
  1. Locate an open or a high resistance in circuits XP1 and/or XP804.
  2. Repair the open or the high resistance in circuits XP1 and/or XP804.

Is the repair complete?

--

Go to Step 17

--

14

Use the DMM to measure the resistance between terminal 2 of the LH roof rail courtesy lamp connector and a known good ground.

Is the measured resistance less than the specified value?

5 ohms

Go to Step 16

Go to Step 15

15
  1. Locate an open or a high resistance in circuits F1 and/or F84.
  2. Repair the open or the high resistance in circuits F1 and/or F84.

Is the repair complete?

--

Go to Step 17

--

16

Replace the LH roof rail courtesy lamp. Refer to Roof Side Rail Lamp Replacement in Lighting Systems.

Is the replacement complete?

--

Go to Step 17

--

17
  1. Connect all connectors and components that were disconnected.
  2. Verify that the LH and RH roof rail courtesy lamps operate properly.

Do the LH and RH roof rail courtesy lamps operate properly?

--

Go to Interior Lamps System Check

Go to Step 1