GM Service Manual Online
For 1990-2009 cars only

Step

Action

Value(s)

Yes

No

1

Was the entire Fog Lights System Check performed?

--

Go to Step 2

Go to Fog Lights System Check

2

Backprobe the rear compartment relay center connector with a DMM from cavity D6 (ORN) to ground.

Is the voltage within the specified range?

10-15 V

Go to Step 3

Go to Step 8

3

  1. Turn the ignition switch to the ON position.
  2. Backprobe the rear compartment relay center connector with a DMM from cavity C6 (PNK) to ground.

Is the voltage within the specified range?

10-15 V

Go to Step 4

Go to Step 14

4

  1. Place the headlamp switch in the ON position.
  2. Connect a scan tool to the data link connector (DLC).
  3. Select INPUTS from the instrument panel integration module (IPM) DATA DISPLAY.
  4. Operate the rear fog lamp switch.

Does the scan tool indicate that the switch is ON when operated and OFF when inactive?

--

Go to Step 5

Go to Step 20

5

  1. Place the rear fog lamp switch in the ON position.
  2. Backprobe the rear compartment relay center connector with a DMM from cavity D6 (ORN) to cavity D4 (YEL).

Is the voltage within the specified range?

10-15 V

Go to Step 6

Go to Step 18

6

Replace the RR FOG LP relay in the rear compartment relay center. Refer to Wiring Repairs in Wiring Systems.

Do both rear fog lamps now operate properly?

--

Go to Fog Lights System Check

Go to Step 7

7

Repair the open in CKT 122 (RED) between the rear compartment relay center and S420. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Fog Lights System Check

--

8

Do the position lamps operate properly?

--

Go to Step 13

Go to Step 9

9

Check the rear junction block EXPORT LGT Fuse for an open.

Is the EXPORT LGT Fuse OK?

--

Go to Step 10

Go to Step 11

10

Repair the open in CKT 3140 (ORN) between the rear junction block and S401. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Fog Lights System Check

--

11

Repair the short to ground in CKT 3140 (ORN). Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Step 12

--

12

Replace the EXPORT LGT Fuse. Refer to Wiring Repairs in Wiring Systems.

Is the fuse replacement complete?

--

Go to Fog Lights System Check

--

13

Repair the open in CKT 3140 (ORN) between the S401 and the rear compartment relay center. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Fog Lights System Check

--

14

Check the rear junction block IGN 1 Fuse for an open.

Is the IGN 1 Fuse OK?

--

Go to Step 17

Go to Step 15

15

Repair the short to ground in CKT 1039 (PNK). Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Step 16

--

16

Replace the IGN 1 Fuse. Refer to Wiring Repairs in Wiring Systems.

Is the IGN 1 Fuse replacement complete?

--

Go to Fog Lights System Check

--

17

Repair the open in CKT 1039 (PNK). Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Fog Lights System Check

--

18

  1. Remove the RR FOG LP relay from the rear compartment relay center.
  2. Disconnect the rear integration module (RIM) connector C2.
  3. Backprobe with a DMM from the rear compartment relay center connector cavity D4 (YEL) to the RIM connector C2 cavity A9 (YEL).

Is the resistance less than the specified value?

5 ohms

Go to Step 19

Go to Step 25

19

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

Is the RIM replacement complete?

--

Go to Fog Lights System Check

--

20

  1. Backprobe the headlamp switch connector with a DMM from battery positive voltage (B+) to cavity A3 (LT BLU).
  2. Press the rear fog lamp switch.

Is the voltage within the specified range?

10-15 V

Go to Step 21

Go to Step 22

21

Repair the open in CKT  187 (LT BLU). Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Fog Lights System Check

--

22

Backprobe the headlamp switch connector with a DMM from battery positive voltage (B+) to cavity A2 (BLK).

Is the voltage within the specified range?

10-15 V

Go to Step 23

Go to Step 24

23

Replace the headlamp switch. Refer to Headlamp Switch Replacement in Instrument Panel, Gauges and Console.

Is the headlamp switch replacement complete?

--

Go to Fog Lights System Check

--

24

Repair the open in CKT 351 (BLK/WHT) between the headlamp switch and S212. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Fog Lights System Check

--

25

Repair the open in CKT 1977 (YEL) between the rear compartment relay center and the RIM. Refer to Wiring Repairs in Wiring Systems.

Is the circuit repair complete?

--

Go to Fog Lights System Check

--