Schematic Reference: Fog Lights Schematics

Did you review the Exterior Lighting System Description and Operation and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Lighting Systems

1. Turn the ignition ON, with the engine OFF.
2. Turn the headlamp switch to the HEAD position.
3. Pull the turn signal lever toward you in order to illuminate the LOW headlamps.
4. Turn the fog lamp switch to the ON position.

Do both front fog lamps operate?

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

Go to Step 3

Is only one front fog lamp inoperative?

Go to Step 12

Go to Step 4

1. Remove the fog lamp relay
2. Probe the switch side feed circuit of the fog lamp relay connector with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 5

Go to Step 11

Install a fused jumper across the switch side feed circuit and the fog lamps supply voltage circuit of the fog lamp relay connector.

Did the fog lamps illuminate?

Go to Step 6

Go to Step 20

Probe the control circuit of the fog lamp relay connector with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 7

Go to Step 8

1. Insure that the high beam headlamps are OFF.
2. Probe the headlamp high beam voltage supply circuit of the fog lamp relay connector with a test lamp that is connected to battery voltage.

Does the test lamp illuminate?

Go to Step 21

Go to Step 18

1. Disconnect the rear window wiper/washer and multifunction switch connector C3.
2. Probe the park lamp supply voltage circuit of the fog lamp switch with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 9

Go to Step 19

1. Connect a fused jumper between the parklamps supply voltage circuit and the fog lamp relay control circuit of the fog lamp switch connector.
2. Probe the control circuit of the fog lamp relay connector with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 22

Go to Step 10

Test the control circuit of the fog lamp relay for a open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 25

Go to Step 20

Test the switch side feed circuit of the fog lamp relay for a open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find an open in the switch side feed circuit of the fog lamp relay?

Go to Step 20

Go to Step 17

1. Remove the inoperative fog lamp bulb.
2. Using a test lamp, probe between the fog lamps supply voltage circuit and the ground circuit of the inoperative fog lamp bulb.

Does the test lamp illuminate?

Go to Step 23

Go to Step 13

1. Disconnect the inoperative fog lamp connector.
2. Probe the supply voltage circuit of the inoperative fog lamp connector with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 14

Go to Step 15

Using a test lamp, probe between the ground circuit and the supply voltage circuit of the inoperative fog lamp connector.

Does the test lamp illuminate?

Go to Step 24

Go to Step 16

Repair the open or high resistance in the supply voltage circuit of the inoperative fog lamp. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

--

Repair the open or high resistance in the ground circuit of the inoperative fog lamp. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

--

Repair the short to ground in the switch side feed circuit or fog lamps supply voltage circuit of the fog lamp relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

--

Repair the open or high resistance in the headlamp high beam voltage supply of the fog lamp relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

--

Repair the open or high resistance in the parklamp supply voltage circuit of the fog lamp switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 25

--

1. Test for poor connections at the junction block - underhood. Refer to Testing for Intermittent Conditions and Poor Connections .
2. If the connections are OK, replace the junction block - underhood. Refer to Underhood Electrical Center or Junction Block Replacement .

Is the repair complete?

Go to Step 25

--

Replace the fog lamp relay.

Is the repair complete?

Go to Step 25

--

Replace the fog lamp switch. Refer to Multifunction Switch Assembly Replacement - Instrument Panel .

Is the repair complete?

Go to Step 25

--

Replace the inoperative front fog lamp bulb. Refer to Front Fog Lamp Replacement .

Is the repair complete?

Go to Step 25

--

Replace the inoperative front fog lamp. Refer to Front Fog Lamp Replacement .

Is the repair complete?

Go to Step 25

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2

Schematic Reference: Fog Lights Schematics

Did you review the Exterior Lighting System Description and Operation and perform the necessary inspections?

Go to Step 2

Go to Symptoms - Lighting Systems

1. Turn the headlamp switch to the HEAD position.
2. Press and release the rear fog lamp switch .

Are both rear fog lamps operating properly?

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

Go to Step 3

Is only one rear fog lamp inoperative?

Go to Step 12

Go to Step 4

Check for an open in the RR FOG LP Fuse.

Is the RR FOG LP Fuse open?

Go to Step 27

Go to Step 5

1. Remove the fog lamp relay.
2. Probe the coil side feed of the rear fog lamp relay connector with a test lamp that is connected ground.
3. Probe the switch side feed of the rear fog lamp relay connector with a test lamp that is connected to ground.

Does the test lamp illuminate for both tests?

Go to Step 6

Go to Step 26

Install a fused jumper across the switch side feed circuit and the fog lamps supply voltage circuit of the rear fog lamp relay connector.

Do the fog lamps illuminate?

Go to Step 7

Go to Step 15

1. Probe the control circuit of the rear fog lamp relay with a test lamp that is connected to a battery voltage.
2. Press and release the rear fog lamp switch.

Does the test lamp illuminate when the fog lamp switch is pressed?

Go to Step 32

Go to Step 8

1. Disconnect the rear fog lamp module.
2. Probe the headlamp switch signal circuit of the rear fog lamp module with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

Go to Step 9

Go to Step 25

Probe the ground circuit of the rear fog lamp module with a test lamp that is connected to battery voltage.

Does the test lamp illuminate?

Go to Step 10

Go to Step 23

1. Probe the fog lamp switch signal circuit of the fog lamp module connector with a test lamp that is connected to a battery voltage.
2. Press and release the rear fog lamp switch.

Does the test lamp illuminate when the rear fog lamp switch is pressed?

Go to Step 17

Go to Step 11

1. Disconnect the window wiper/washer and multifunction switch connector.
2. Probe the ground circuit of the fog lamp switch connector with a test lamp that is connected to battery voltage.

Does the test lamp illuminate?

Go to Step 16

Go to Step 28

1. Remove the inoperative fog lamp bulb.
2. Using a test lamp, probe between the fog lamps supply voltage circuit and the ground circuit of the inoperative fog lamp bulb.

Does the test lamp illuminate?

Go to Step 29

Go to Step 13

1. Disconnect the taillamp connector of the inoperative fog lamp.
2. Probe the fog lamp supply voltage circuit of the inoperative taillamp connector with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 14

Go to Step 18

Using a test lamp, probe between the ground circuit and the fog lamp supply voltage circuit of the inoperative taillamp connector.

Does the test lamp illuminate?

Go to Step 31

Go to Step 19

1. Disconnect one of the taillamp connectors.
2. Probe the fog lamp supply voltage circuit of the taillamp connector with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 20

Go to Step 24

1. Connect a fused jumper between the switch signal circuit and the ground circuit of the fog lamps switch connector.
2. Probe the fog lamp switch signal circuit of the fog lamp module connector with a test lamp that is connected to a battery voltage.

Does the test lamp illuminate?

Go to Step 30

Go to Step 21

1. Connect a fused jumper between the fog lamp relay control circuit of the fog lamps module connector and the ground.
2. Probe the control circuit of the fog lamp relay connector with a test lamp that is connected to a battery voltage.

Does the test lamp illuminate?

Go to Step 33

Go to Step 22

Repair the open or high resistance in the supply voltage circuit of the inoperative fog lamp. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 34

--

Repair the open or high resistance in the ground circuit of the inoperative fog lamp. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 34

--

Repair the open or high resistance in the ground circuit of the fog lamps. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 34

--

Repair the open or high resistance in the signal circuit of the rear fog lamp switch. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 34

--

Repair the open or high resistance in the control circuit of the rear fog lamp relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 34

--

Repair the open or high resistance in the ground circuit of the rear fog lamp module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 34

--

Repair the open or high resistance in the supply voltage circuit of the fog lamps. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 34

--

Repair the open or high resistance in the headlamp switch signal circuit of the rear fog lamp module. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 34

--

Repair the open or high resistance in the coil feed circuit or the switch side feed circuit of the rear fog lamp relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 34

--

Repair the short to ground in the battery positive voltage circuit of the fog lamp relay or the fog lamp supply voltage circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 34

--

Repair the open or high resistance in the rear fog lamp switch ground circuit. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 34

--

Replace the inoperative rear fog lamp bulb. Refer to Tail Lamp Replacement .

Has the repair been made and the system rechecked?

Go to Step 34

--

Replace the rear window wiper/washer and multifunction switch. Refer to Multifunction Switch Assembly Replacement - Instrument Panel .

Has the repair been made and the system rechecked?

Go to Step 34

--

Replace the taillamp assemble that houses the inoperative fog lamp. Refer to Tail Lamp Replacement .

Has the repair been made and the system rechecked?

Go to Step 34

--

Replace the rear fog lamp relay.

Has the repair been made and the system rechecked?

Go to Step 34

--

Replace the rear fog lamp module.

Has the repair been made and the system rechecked?

Go to Step 34

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2