Mazda 2002 6 - Dtc B2391

T–146–4
ON-BOARD DIAGNOSTIC [DISCHARGE HEADLIGHT]
End Of Sie
DTC B2391
A6E818867000W09
Diagnostic procedure
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 T–25 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.
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.
(See T–26 FRONT COMBINATION LIGHT REMOVAL/
INSTALLATION)
HEADLIGHT (LH)
HARNESS SIDE CONNECTOR
1K 1I
1G 1E
1H 1F1L 1J
1C 1A
1D 1B
HEADLIGHT (RH)
HARNESS SIDE CONNECTOR
1K 1I
1G 1E
1H 1F1L 1J
1C 1A
1D 1B