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Circuit/System Testing

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DTC B19A0

  1. Ignition OFF, exterior lamps OFF, disconnect the connector at the E7AC Rear License Plate Lamp Module.
  2. Connect a test lamp between control circuit terminal 2 and ground circuit terminal 1 at the electrical connector, ignition ON:
  3. Verify the test lamp turns ON and OFF while commanding the License Plate Lamps Command ON and OFF with the scan tool.
    • If the test lamp is always OFF 
    1. Test circuit 1650 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit or ground connection.
      • Go to next step: If an open/high resistance is not found
    2. Test circuit 6846 for an open/high resistance.
      • If an open/high resistance is found, repair the fault on the circuit.
      • Go to next step: If an open/high resistance is not found
    3. Test circuit 6846 for a short to ground.
      • If a short to ground is found, repair the fault on the circuit.
      • Go to next step: If a short to ground is not found
    4. Replace the K219 Lighting Control Module.
    • If the test lamp is always ON 
    1. Test circuit 6846 for a short to voltage.
      • If a short to voltage is found, repair the fault on the circuit.
      • Go to next step: If a short to voltage is not found
    2. Replace the K219 Lighting Control Module.
    • Go to next step: If the test lamp turns ON and OFF 
  4. Replace the E7AC Rear License Plate Lamp Module.
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