GM Service Manual Online
For 1990-2009 cars only

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Action

Yes

No

Schematic Reference: Interior Lights Schematics

Connector End View Reference: Master Electrical Component List in Wiring Systems.

1

Did you perform the Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Turn the ignition to the ON position, with the engine OFF.
  2. Turn the headlamp switch to the PARK position.

Do all of the park lamps illuminate?

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

Go to Step 3

3

Is only one lamp inoperative?

Go to Step 15

Go to Step 4

4

  1. Disconnect the multifunction switch connector C3.
  2. Connect a test lamp between battery positive voltage and the ground circuit of the park lamp switch at the headlamp connector.

Does the test lamp illuminate?

Go to Step 5

Go to Step 6

5

  1. Install a jumper between the park lamp switch ON signal circuit and the park lamp switch ground circuit.
  2. Place the ignition in the ON position, with the engine OFF.

Do the park lamps illuminate?

Go to Step 13

Go to Step 7

6

Repair a poor connection or an open in the ground circuit of the park lamp switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 19

--

7

Test for a poor connection, and open or a short to battery positive voltage in the park lamp switch ON signal circuit.

Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 19

Go to Step 8

8

  1. Reconnect the multifunction switch connector C3.
  2. Remove the park lamp relay in the underhood electrical center.
  3. Install a fused jumper between the park lamp relay coil supply circuit and the park lamp switched voltage supply circuit.

Do the park lamps illuminate?

Go to Step 10

Go to Step 9

9

Test for a short to ground in the park lamps switched voltage supply circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 19

Go to Step 17

10

  1. Reinstall the park lamp relay.
  2. Disconnect the BCM connector C1.
  3. Install a 10A fused jumper between the park lamp relay control circuit and ground.

Do the park lamps illuminate?

Go to Step 16

Go to Step 11

11

Test for a short to battery positive voltage, an open or a poor connection in the park lamp relay control circuit. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 19

Go to Step 12

12

Replace the park lamp relay. Refer to Relay Replacement in Wiring Systems.

Did you complete the repair?

Go to Step 19

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13

Inspect for poor connections at the harness connector of the multifunction 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 19

Go to Step 18

14

Repair a short to battery positive voltage an open or a poor connection in the park lamp switch circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 19

--

15

Repair the poor connection or an open in the inoperative park lamp voltage supply circuit or ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 19

--

16

Important: After replacing the BCM perform the setup procedure. Refer to Body Control Module (BCM) Programming/RPO Configuration in Computer/Integrating Systems.

Replace the BCM. Refer to Body Control Module Replacement in Computer/Integrating Systems.

Did you complete the replacement?

Go to Step 19

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17

Replace the underhood electrical center. Refer to Underhood Electrical Center or Junction Block Replacement in Wiring Systems.

Did you complete the replacement?

Go to Step 19

--

18

Replace the multifunction switch. Refer to Turn Signal Multifunction Switch Replacement in Steering Wheel and Column.

Did you complete the replacement?

Go to Step 19

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19

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 3