Battery voltage is applied at all times to both front cornering lamp PCB relays which are an internal part of the underhood fuse block. When the turn signal switch is activated, ground is applied through the turn signal switch signal circuit to the body control module (BCM) The BCM then applies a ground to the appropriate cornering lamp relay control circuit energizing the relay. With the relay energized, battery voltage is applied through the switch side of the relay, the LT or RT CRN LAMP Fuse, and the cornering lamp supply voltage circuit to the cornering lamp.

Schematic Reference

Exterior Lights Schematics

Connector End View Reference

Lighting Systems Connector End Views

Electrical Information Reference

Scan Tool Reference

Ignition ON, operate the left and right turn signal and observe the related cornering lamp. The cornering lamp should illuminate as long as the turn signal is ON.

1. Ignition ON, park or headlamps ON, place the turn signal switch in the direction of the inoperative cornering lamp.
2. With a test lamp connected to ground, probe each of the test points on the appropriate CRN LAMP Fuse. The test lamp should illuminate at one or both of the fuse test points.

⇒	If the test lamp does not illuminate at either test point or remains illuminated at all times with the turn signal OFF, refer to the Corner Lamp PCB Relay Circuit Test.

⇒	If the test lamp illuminates, refer to the Cornering Lamp Circuit Test.

Corner Lamp PCB Relay Circuit Test

1. Ignition OFF, disconnect the (C2) harness connector at the underhood fuse block.
2. Connect a test lamp between battery voltage and the appropriate control circuit terminal listed below.

•	Left cornering lamp relay control terminal 3

•	Right cornering lamp relay control terminal 2

3. Ignition ON, park or headlamps ON, operate the turn signal switch ON and OFF. The test lamp should turn ON and OFF when changing between the commanded states.

⇒	If the test lamp is always ON, test the control circuit for a short to ground. If the circuit tests normal, replace the BCM.

⇒	If the test lamp is always OFF, test the control circuit for a short to voltage or an open/high resistance. If the circuit tests normal, replace the BCM.

4. If the circuit tests normal, replace the underhood fuse block.

Cornering Lamp Circuit Test

1. Ignition OFF, disconnect the harness connector at the inoperative cornering lamp/headlamp assembly.
2. Ignition OFF, test for less than 5.0 ohms of resistance between the ground circuit terminal E and ground.

⇒	If greater than the specified range, test the ground circuit for and open/high resistance.

3. Connect a test lamp between the supply voltage circuit terminal A and ground.
4. Ignition ON, park or headlamps ON, operate the turn signal switch ON and OFF, The test lamp should turn ON and OFF when changing between the commanded states.

⇒	If the test lamp is always ON, test the supply voltage circuit for a short to voltage. If the circuit tests normal, replace the underhood fuse block

⇒	If the test lamp is always OFF, test the supply voltage circuit for a short to ground or an open/high resistance. If the circuit tests normal, test or replace the underhood fuse block.

5. If all circuits test normal, test or replace the cornering lamp bulb.

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.