GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the entire Exterior Lights System Check performed?

--

Go to Step 2

Go to Exterior Lights System Check

2

  1. Turn the ignition switch to the ON position.
  2. Connect a scan tool to the data link connector (DLC).
  3. Select INPUTS from the dash integration module (DIM) DATA DISPLAY.
  4. Place the headlamp switch in the PARK position.

Does the scan tool indicate that the Park Lamps Switch was ON?

--

Go to Step 3

Go to Step 7

3

Do the headlamps operate properly?

--

Go to Step 4

Go to Step 12

4

Backprobe the rear junction block connector C1 with a test lamp from battery positive voltage (B+) to cavity F3 (WHT).

Does the test lamp light?

--

Go to Step 5

Go to Step 14

5

Replace the PRK LP Relay. Refer to Wiring Repairs in Wiring Systems.

Do all park lamps now operate properly?

--

Go to Exterior Lights System Check

Go to Step 6

6

Replace the rear junction block. Refer to Rear Junction Block Replacement.

Is the rear junction block replacement complete?

--

Go to Exterior Lights System Check

--

7

Backprobe the headlamp switch connector C202 with a test lamp from battery positive voltage (B+) to cavity C2 (BRN/WHT).

Does the test lamp light?

--

Go to Step 8

Go to Step 9

8

Repair the open in CKT 301 (BRN/WHT) between the dash integration module (DIM) and the headlamp switch. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Exterior Lights System Check

--

9

Backprobe the headlamp switch connector C202 with a test lamp from battery positive voltage (B+) to cavity B7 (BLK).

Does the test lamp light?

--

Go to Step 10

Go to Step 11

10

Replace the headlamp switch. Refer to Cruise Control Switch Assembly - Pivot and Pulse in Steering Wheel and Column-Tilt.

Is the headlamp switch replacement complete?

--

Go to Exterior Lights System Check

--

11

Repair the open in CKT 450 (BLK) between the headlamp switch and G201. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Exterior Lights System Check

--

12

Backprobe the rear junction block connector C1 with a test lamp from cavity D4 (DK GRN) to ground.

Does the test lamp light?

--

Go to Step 6

Go to Step 13

13

  1. Remove the PRK LP relay from the rear junction block.
  2. Disconnect the dash integration module (DIM) connector C1.
  3. Backprobe with a DMM from the rear junction block connector C1 cavity D4 (DK GRN) to the DIM connector C1 cavity B8 (DK GRN).

Is the resistance less than the specified value?

5 ohms

Go to Step 15

Go to Step 16

14

  1. Remove the PRK LP relay from the rear junction block.
  2. Disconnect the dash integration module (DIM) connector C1.
  3. Backprobe with a DMM from the rear junction block connector C1 cavity F3 (WHT) to the DIM connector C1 cavity B5 (WHT).

Is the resistance less than the specified value?

5 ohms

Go to Step 15

Go to Step 17

15

Replace the dash integration module (DIM). Refer to Body Control Module Replacement in Body Control System.

Is the DIM replacement complete?

--

Go to Exterior Lights System Check

--

16

Repair the open in CKT 1483 (DK GRN) between the rear junction block and the DIM. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Exterior Lights System Check

--

17

Repair the open in CKT 1080 (WHT) between the rear junction block and the DIM. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Exterior Lights System Check

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