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Circuit/System Testing

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  1. Ignition OFF, disconnect the X4 harness connector of the APM.
  2. Verify that a test lamp illuminates between the ground circuit of the APM and B+.
    • If the test lamp does not illuminate, test the circuit for an open/high resistance. If the circuit tests normal, replace the APM.
  3. Ignition OFF, disconnect the X3 harness connector of the APM.
  4. Ignition ON, verify that a test lamp illuminates between the B+ circuit terminal A and ground.
    • If the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the APM.
  5. Ignition OFF, disconnect X1 harness connector of the PIM and the X1 harness connector of the APM.
  6. Test for less than 1.0 ohm between the PIM and the APM on the following circuit terminals.
    • PTLAN + PIM terminal 24 and APM terminal 2
    • PTLAN - PIM terminal 25 and APM terminal 1
    • If greater than the specified range, test the circuit for an open/high resistance.
  7. If the circuits test normal, replace the PIM.
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