For 1990-2009 cars

### Diagnostic Instructions

• | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.

• | Review Strategy Based Diagnosis for an overview of the diagnostic approach.

• | Diagnostic Procedure Instructions provides an overview of each diagnostic category.

### DTC Descriptor

DTC B2590 02: Left Cornering Lamp Circuit Short to Ground
DTC B2590 04: Left Cornering Lamp Circuit Open
DTC 2595 02: Right Cornering Lamp Circuit Short to Ground
DTC 2595 04: Right Cornering Lamp Circuit Open

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Ignition 1 | 2 | 2 | -- | --
Ignition 2 | 1 | 1 | -- | --
Left Headlamp Control | B2575 00 | B2575 04 | 2 | --
Right Headlamp Control | B2699 00 | B2575 04 | 2 | --
Cornering Lamp Voltage Supply | B2575 00, B2699 00 | 1 | -- | --
Headlamp Ground | -- | 1 | -- | --
1. Left Cornering Lamp Inoperative 2. Right Cornering Lamp Inoperative 3. Left Cornering Lamp always ON 4. Right Cornering Lamp always ON

### Circuit/System Description

The cornering lamp is activated automatically at vehicle speeds below 40 km/h (25 MPH) when the direction indicator is switched ON and/or when the steering angle is changed from the straight-ahead position towards the side the vehicle is going to turn and passes a programmable angle threshold. The cornering lamp is deactivated automatically when the direction indicator is switched OFF and/or the steering angle has returned in the straight-ahead position. The cornering lamps are deactivated at vehicle speeds above 40 km/h (25 MPH). If reverse gear is active, the cornering lamps go into park function. Both lamps will be switched on. They will switch off 20 s after leaving reverse gear or if the vehicle speed exceeds 7 km/h (4 MPH). The cornering lamps also provide a protection against overheating. When having been continuously switched on for 2 min, automatic headlamp leveling will deactivate the lamps for 2 min to enable cooling down.

### Conditions for Running the DTC

The headlamp control module will attempt to switch ON the cornering lights.

### Conditions for Setting the DTC

#### B2590 02 or B2595 02

The DTC will set when the headlamp control module detects low voltage on the sensor control circuit.

#### B2590 04 or B2595 04

The DTC will set when the headlamp control module detects no signal and high voltage on the sensor signal line.

### Action Taken When the DTC Sets

• | The headlamp control module will not attempt to switch ON the cornering lights.

• | Advanced front lighting system fault indication ON

### Conditions for Clearing the DTC

The condition responsible for setting the DTC no longer exists.

### Reference Information

#### Schematic Reference

Headlight Leveling Schematics

#### Connector End View Reference

Component Connector End Views

#### Description and Operation

Exterior Lighting Systems Description and Operation

#### Electrical Information Reference

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

#### Scan Tool Reference

Control Module References for scan tool information

### Circuit/System Verification

1. Verify that DTC B3415 is not present.

⇒ | If DTC is present, refer to DTC B3415

### Circuit/System Testing

1. Ignition OFF, disconnect the harness connector at the appropriate headlamp assembly.
2. Ignition OFF, test for less than 5 Ω between the ground circuit terminal 1 and ground.

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

3. Ignition OFF, disconnect the harness connector X2 at the K26 Headlamp Control Module.
4. Ignition ON, verify that a test lamp illuminates between the ignition 1 circuit terminal 1 and ground

⇒ | If the test lamp does not illuminate, test the ignition 1 circuit for open/high resistance or short to ground.

5. Ignition ON, verify that a test lamp illuminates between the ignition 2 circuit terminal 2 and ground

⇒ | If the test lamp does not illuminate, test the ignition 2 circuit for open/high resistance or short to ground.

6. Reconnect the harness connector at the K26 Headlamp Control Module.
7. Ignition ON, connect a test lamp between the control circuit terminal 9 at the appropriate headlamp assembly. Command the appropriate Cornering Lamp test ON and OFF with the scan tool, verify that the test lamp changes between turn ON and OFF.

⇒ | If the test lamp is always ON, test the control circuit for a short to voltage. If the circuit tests normal, replace the K26 Headlamp Control Module.

⇒ | If the test lamp is always OFF, test the control circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K26 Headlamp Control Module.

8. If all circuits test normal, replace the appropriate headlamp assembly or bulb.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | Headlamp Replacement

• | Control Module References for headlamp control module replacement, setup, and programming