GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the Exterior Lights System Check performed?

--

Go to Step 2

Go to Exterior Lights System Check

2

  1. Connect a scan tool to the data link connector (DLC).
  2. Inspect the IPC park lamp switch input.

Does the park lamp switch operate properly?

--

Go to Step 3

Go to Step 8

3

  1. Remove the park lamps relay from the rear compartment relay center 2.
  2. Measure the voltage to ground at the park lamps relay connector terminal A4 (RED).

Is battery voltage measured?

--

Go to Step 4

Go to Step 11

4

Connect a fused jumper between the park lamps relay connector terminal A4 (RED) and terminal B6 (PPL).

Do the park lamps turn on?

--

Go to Step 5

Go to Step 12

5

  1. Set the headlamps switch to the PARK position.
  2. Measure the voltage between the park lamps relay connector terminal A6 (WHT) and terminal B4 (GRY/BLK).

Is battery voltage measured?

--

Go to Step 6

Go to Step 7

6

Inspect CKT 308 (GRY/BLK) for an open between the rear compartment relay center 2 and the body control module (PZM). Refer to Testing for Continuity in Wiring Systems.

Is CKT 308 OK?

--

Go to Step 13

Go to Step 18

7

Inspect CKT 352 (WHT) for an open or short to ground. Refer to Testing for Continuity or Testing for Short to Ground in Wiring Systems.

Is CKT 352 OK?

--

Go to Step 14

Go to Step 18

8

  1. Disconnect the headlamp switch connector.
  2. Ground terminal D (LT BLU) of the headlamp switch connector C1 with a fused jumper.

Is the IPC park lamp switch input on?

--

Go to Step 9

Go to Step 10

9

Inspect CKT 151 (BLK/WHT) for an open between the headlamp switch and S216. Refer to Testing for Continuity in Wiring Systems.

Is CKT 151 OK?

--

Go to Step 16

Go to Step 18

10

Inspect CKT 74 (LT BLU) for an open. Refer to Testing for Continuity in Wiring Systems.

Is CKT 74 OK?

--

Go to Step 17

Go to Step 18

11

Repair the open or short to ground in CKT 1342 (RED). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Exterior Lights System Check

--

12

Repair the open or short to ground in CKT 256 (PPL). Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Exterior Lights System Check

--

13

Replace the park lamps relay.

Is the park lamps relay replacement complete?

--

Go to Exterior Lights System Check

--

14

Inspect CKT 308 (GRY/BLK) for an open between the rear compartment relay center 2 and the headlamp switch. Refer to Testing for Continuity in Wiring Systems.

Is CKT 308 OK?

--

Go to Step 15

Go to Step 18

15

Replace the body control module (PZM). Refer to Body Control Module Replacement in Body Control Systems.

Is the body control module replacement complete?

--

Go to Exterior Lights System Check

--

16

Replace the headlamp switch. Refer to Headlamp Switch Replacement .

Is the headlamp switch replacement complete?

--

Go to Exterior Lights System Check

--

17

Replace the instrument cluster IPC. Refer to Instrument Cluster Replacement in Instrument Panel, Gauges and Console.

Is the IPC replacement complete?

--

Go to Exterior Lights System Check

--

18

Repair the suspect wiring. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Exterior Lights System Check

--