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Circuit/System Testing

  1. Ignition OFF, disconnect the harness connector X1 at the PIM.
  2. Test for less than 5 ohms between the PIM case and ground.
    • If greater than the specified range, test the ground strap for an open/high resistance. If the circuit tests normal, replace the PIM.
  3. Ignition ON, verify that a test lamp illuminates between the following voltage circuit terminals of the PIM and ground.
    • Terminal 6
    • Terminal 7
    • Terminal 20
    • If the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance.
  4. Ignition ON, verify that a test lamp illuminates between the signal circuit terminal 19 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 SDGM.
  5. Ignition OFF, disconnect the harness connector X3 at the engine control module.
  6. Test for less than 1.0 ohm on the high speed hybrid GMLAN serial data circuits between the following ECM and PIM circuit terminals.
    • ECM X 3 terminal 53 and PIM X 1 terminal 11
    • ECM X 3 terminal 33 and PIM X 1 terminal 10
    • If greater than the specified range, test the circuit for open/high resistance
  7. If all circuits test normal, replace the PIM.
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