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. Turn the fog lamp switch ON.
3. Turn the headlamp dimmer switch to the LOW BEAM position.

Do the fog lamps operate properly?

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

Go to Step 3

Is only one fog lamp inoperative?

Go to Step 8

Go to Step 4

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

Does the test lamp illuminate?

Go to Step 5

Go to Step 10

Probe the headlamp high beam supply circuit of the fog lamp relay with a test lamp that is connected to battery voltage.

Does the test lamp illuminate?

Go to Step 6

Go to Step 17

Probe the park lamps supply voltage circuit of the fog lamp relay with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 7

Go to Step 15

Connect a fused jumper between park lamps supply voltage circuit and the fog lamps supply voltage circuit of the fog lamp relay.

Do the fog lamps illuminate?

Go to Step 12

Go to Step 20

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

Does the test lamp illuminate?

Go to Step 9

Go to Step 19

Probe between the ground circuit and the supply voltage circuit of the inoperative fog lamp with a test lamp.

Does the test lamp illuminate?

Go to Step 14

Go to Step 18

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

Does the test lamp illuminate?

Go to Step 11

Go to Step 16

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

Did you find and correct the condition?

Go to Step 24

Go to Step 13

Inspect for poor connections at the harness connector of the fog lamp relay. 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 24

Go to Step 21

Inspect for poor connections at the harness connector of the fog lamp 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 24

Go to Step 22

Inspect for poor connections at the harness connector of the inoperative front fog lamp. 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 24

Go to Step 23

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

Did you complete the repair?

Go to Step 24

--

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

Did you complete the repair?

Go to Step 24

--

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

Did you complete the repair?

Go to Step 24

--

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

Did you complete the repair?

Go to Step 24

--

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

Did you complete the repair?

Go to Step 24

--

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

Did you complete the repair?

Go to Step 24

--

Replace the fog lamp relay. Refer to Fog Lamp Relay Replacement .

Did you complete the replacement?

Go to Step 24

--

Replace the fog lamp switch. Refer to Fog Lamp Switch Replacement .

Did you complete the replacement?

Go to Step 24

--

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

Did you complete the replacement?

Go to Step 24

--

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 perform the Lighting Systems Diagnostic System Check?

Go to Step 2

Go to Diagnostic System Check - Lighting Systems

1. Turn the headlamps on.
2. Turn the front fog lamp switch on.
3. Turn the rear fog lamp switch on.

Do the rear fog lamps illuminate?

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

Go to Step 3

Is only one fog lamp inoperative?

Go to Step 14

Go to Step 4

Do the front fog lamps operate properly?

Go to Step 5

Go to Fog Lamps Inoperative

1. Remove the fog lamp relay.
2. Probe the park lamp supply circuit of the rear fog lamp relay with a test lamp that is connected to ground.

Do the rear fog lamps turn on?

Go to Step 6

Go to Step 18

Connect a fused jumper between the park lamp supply voltage circuit of the rear fog lamp relay and the fog lamps supply voltage circuit of the rear fog lamp relay.

Go to Step 7

Go to Step 13

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

Go to Step 8

Go to Step 9

Probe the supply voltage circuit of the rear fog lamp relay coil with a test lamp that is connected to ground.

Go to Step 28

Go to Step 12

1. Disconnect the rear fog lamp switch.
2. Probe the ground circuit of the rear fog lamp switch with a test lamp that is connected to battery voltage.

Does the test lamp illuminate?

Go to Step 10

Go to Step 19

1. Connect the rear fog lamp switch.
2. Place the rear fog lamp switch in the ON position.
3. Backprobe the signal circuit of the rear fog lamp switch with a test lamp that is connected to battery voltage.

Does the test lamp illuminate?

Go to Step 11

Go to Step 27

1. Disconnect the Body Control Module (BCM).
2. Probe the fog lamp switch signal circuit of the BCM with a test lamp that is connected to battery voltage.

Does the test lamp illuminate?

Go to Step 16

Go to Step 20

1. Disconnect the diode module.
2. Probe the fog lamp relay coil supply voltage circuit of the diode module with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 17

Go to Step 21

1. Leave the fused jumper connected.
2. Disconnect one of the rear fog lamps.
3. Probe the supply voltage circuit of the rear fog lamp connector with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 24

Go to Step 22

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

Does the test lamp illuminate?

Go to Step 15

Go to Step 23

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

Does the test lamp illuminate?

Go to Step 26

Go to Step 24

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

Did you find and complete the repair?

Go to Step 30

Go to Step 29

Test for an open or high resistance in the fog lamp relay coil supply voltage circuit of the rear fog lamp relay. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and complete the repair?

Go to Step 30

Go to Step 25

Repair an open or high resistance in the park lamp supply voltage circuit of the rear fog lamp relay. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 30

--

Repair an open or high resistance in the ground circuit of the rear fog lamp switch. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 30

--

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

Did you complete the repair?

Go to Step 30

--

Repair an open or high resistance in the supply voltage circuit of the diode module. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 30

--

Repair an open or high resistance in the supply voltage circuit of the rear fog lamps. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 30

--

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

Did you complete the repair?

Go to Step 30

--

Repair an open or high resistance in the ground circuit of the inoperative rear fog lamp(s). Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 30

--

Replace the diode module.

Did you complete the replacement?

Go to Step 30

--

Replace the inoperative rear fog lamp. Refer to Rear Fog Lamp Bulb Replacement .

Did you complete the replacement?

Go to Step 30

--

Replace the rear fog lamp switch. Refer to Rear Fog Lamp Switch Replacement .

Did you complete the replacement?

Go to Step 30

--

Replace the rear fog lamp relay. Refer to Fog Lamp Relay Replacement .

Did you complete the replacement?

Go to Step 30

--

Important: Perform the set up procedure for the body control module (BCM). Refer to Body Control Module (BCM) Programming/RPO Configuration in Body Control System.

Replace the BCM. Refer to Body Control Module Replacement in Body Control System.

Did you complete the replacement?

Go to Step 30

--

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. Turn the fog lamp switch ON.

Do the fog lamps operate properly?

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

Go to Step 3

Is only one fog lamp inoperative?

Go to Step 8

Go to Step 4

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

Does the test lamp illuminate?

Go to Step 5

Go to Step 10

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

Does the test lamp illuminate?

Go to Step 6

Go to Step 17

Probe the park lamps supply voltage circuit of the fog lamp relay with a test lamp that is connected to ground.

Does the test lamp illuminate?

Go to Step 7

Go to Step 15

Connect a fused jumper between park lamps supply voltage circuit and the fog lamps supply voltage circuit of the fog lamp relay.

Do the fog lamps illuminate?

Go to Step 12

Go to Step 20

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

Does the test lamp illuminate?

Go to Step 9

Go to Step 19

Probe between the ground circuit and the supply voltage circuit of the inoperative fog lamp with a test lamp.

Does the test lamp illuminate?

Go to Step 14

Go to Step 18

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

Does the test lamp illuminate?

Go to Step 11

Go to Step 16

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

Did you find and correct the condition?

Go to Step 24

Go to Step 13

Inspect for poor connections at the harness connector of the fog lamp relay. 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 24

Go to Step 21

Inspect for poor connections at the harness connector of the fog lamp 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 24

Go to Step 22

Inspect for poor connections at the harness connector of the inoperative front fog lamp. 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 24

Go to Step 23

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

Did you complete the repair?

Go to Step 24

--

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

Did you complete the repair?

Go to Step 24

--

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

Did you complete the repair?

Go to Step 24

--

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

Did you complete the repair?

Go to Step 24

--

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

Did you complete the repair?

Go to Step 24

--

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

Did you complete the repair?

Go to Step 24

--

Replace the fog lamp relay. Refer to Fog Lamp Relay Replacement .

Did you complete the replacement?

Go to Step 24

--

Replace the fog lamp switch. Refer to Fog Lamp Switch Replacement .

Did you complete the replacement?

Go to Step 24

--

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

Did you complete the replacement?

Go to Step 24

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2