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Home >> Suzuki >> 2007 >> XL7 Base, AWD >> Repair and Diagnosis >> Accessories & Equipment >> Headlights >> Lighting Systems >> Diagnostic Information and Procedures >> DTC B257A >> Circuit/System Testing
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Circuit/System Testing

  1. Headlamp switch to OFF, disconnect the BCM connector C2.
  2. Ignition to ON, connect a test lamp between the headlamp OFF switch circuit and the positive battery terminal.

    Verify the test lamp illuminates.

    • If the test lamp does not illuminate:
    • Test for a short to voltage or an open in the headlamp OFF switch circuit.
    • Test for an open in the headlamp ground circuit.
    • If the circuit/connections test normal replace the headlamp switch.
  3. Headlamp switch to PARK, verify the test lamp is not illuminated.
    • If the test lamp illuminates, test for a short to ground in the headlamp OFF switch circuit. If the circuit/connections test normal, replace the headlamp switch.
  4. Headlamp switch to PARK, connect a test lamp between the park lamp switch ON circuit and the positive battery terminal. Verify the test lamp illuminates.
    • If the test lamp does not illuminate, test for a short to voltage or an open in the park lamp switch ON circuit.

      If the circuit/connections test normal, replace the headlamp switch.

  5. Headlamp switch to OFF, verify the test lamp does not illuminate.
    • If the test lamp does illuminate, test for a short to ground in the park lamp switch ON circuit. If the circuit/connections test normal, replace the headlamp switch.
  6. If all circuit/connections test normal, replace the BCM.
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