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Circuit/System Testing

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  1. Ignition OFF, disconnect the harness connector X1 at the APM.
  2. Ignition ON, verify that a test lamp illuminates between the wake up signal circuit terminal 3 and ground.
    • If the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance.
  3. Ignition OFF and scan tool disconnected, verify that a test lamp does not illuminate between the signal circuit terminal 3 and ground.
    • If the test lamp illuminates, test the circuit for a short to voltage.
  4. If all circuits test normal, replace the APM.
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