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Circuit/System Testing

  1. Ignition OFF, disconnect harness connector X1 of the APM.
  2. Test for less than 0.5 volts between the wake up signal circuit terminal 3 and ground.
    • If greater than the specified range, test the signal circuit for a short to voltage. If the circuit tests normal, replace the SDGM.
  3. Disconnect harness connector X1 of the PIM.
  4. Test for B+ between the wake up signal circuit terminal 19 and ground.
    • If less than the specified value, test the circuit for an open/high resistance. If the circuit tests normal, replace the SDGM.
  5. Test for less than 1.0 ohm between the APM and the PIM on the following circuit terminals.
    • PTLAN + APM terminal 2 and PIM terminal 25
    • PTLAN - APM terminal 1 and PIM terminal 24
    • If greater than the specified range, test the circuit for an open/high resistance.
  6. Ignition OFF, disconnect harness connector X3 of the engine control module (ECM).
  7. Test for less than 1.0 ohm between the APM and the ECM on the following circuit terminals.
    • PTLAN + APM terminal 11 and ECM terminal 53
    • PTLAN - APM terminal 10 and ECM terminal 33
    • If greater than the specified range, test the circuit for an open/high resistance.
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