DTC B2391

id0902b2855100

DTC B2391

Discharge headlight input resistance too high

DETECTION CONDITION

Warning
• Incorrect servicing of the discharge headlight control unit could result in electrical shock. Before servicing the discharge headlight control unit, always refer to "Discharge headlight service warnings". (See DISCHARGE HEADLIGHT SERVICE WARNINGS)
• Discharge headlight does not illuminate because of voltage drops caused by high impedance on input path for supply voltage.

POSSIBLE CAUSE

• Resistance in related wiring harness too high
• Resistance in front combination light internal harness too high.

Diagnostic procedure

STEP

INSPECTION

ACTION

1
INSPECT CONNECTOR CONNECTION
• Check fit of discharge headlight control unit and headlight connectors.
• Are installation condition and fit okay?
Yes
Go to next step.
No
After correcting fit, clear DTC and check DTC again.
• If DTC is displayed again, go to next step.
2
INSPECT WIRING HARNESS
• Disconnect headlight connector (12-pin).
• Measure resistance of headlight connector terminal 1C to battery negative terminal.
• Measure resistance of headlight connector terminal 1B to battery positive terminal.
• Is sum of resistances more than 1.5 ohms?
Yes
Repair related wiring harness.
No
Front combination light internal harness may have too high impedance. Replace front combination light.