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Circuit/System Testing

  1. Ignition OFF, test for less than 1.0 Ω between the drive motor generator power inverter module case and ground strap.
    • If greater than the specified value, test the ground circuit for an open/high resistance.
  2. Ignition OFF, disconnect the harness connector X1 of the drive motor generator power inverter module.
  3. Ignition ON, verify that a test lamp illuminates between each of the following B+ circuit terminals and ground.
    • Terminal 6 X1
    • Terminal 7 X1
    • If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit fuse is open, test the control circuits of the drive motor generator power inverter module for a short to ground. If the circuits test normal, replace the drive motor generator power inverter module.
  4. Ignition ON, verify that a test lamp illuminates between each ignition circuit terminal 20 X1 and ground.
    • If the test lamp does not illuminate, test the ignition circuit for a short to ground or an open/high resistance. If the circuit fuse is open, test the control circuits of the drive motor generator power inverter module for a short to ground. If the circuits test normal, replace the drive motor generator power inverter module.
  5. Ignition ON, verify that a test lamp illuminates between the wakeup circuit terminal 19 X1 and ground.
    • If the test lamp does not illuminate, test the entire circuit for an open/high resistance or short to ground. If the circuits test normal, replace the serial data gateway (SDG) module.
  6. Ignition OFF, disconnect the harness connector X1 of the accessory DC power control module.
  7. Test for less than 2 Ω between the following powertrain serial data circuit terminals.
    • Accessory DC power control module terminal 2 X1 and drive motor generator power inverter module terminal 25 X1
    • Accessory DC power control module terminal 1 X1 and drive motor generator power inverter module terminal 24 X1
    • If greater than the specified range, test the circuit for an open/high resistance.
  8. Ignition OFF, disconnect the harness connector X3 of the engine control module (ECM).
  9. Test for less than 2 Ω between the following powertrain serial data circuit terminals.
    • Drive motor generator power inverter module terminal 11 X1 and ECM terminal 53 X3
    • Drive motor generator power inverter module terminal 10 X1 and ECM terminal 33 X3
    • If greater than the specified range, test the circuit for an open/high resistance.
  10. If all circuits test normal, replace the drive motor generator power inverter module.
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