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Circuit/System Testing

WARNING:

Always perform the High Voltage Disabling procedure prior to servicing any High Voltage component or connection. Personal Protection Equipment (PPE) and proper procedures must be followed.

The High Voltage Disabling procedure includes the following steps:

  • Identify how to disable high voltage.
  • Identify how to test for the presence of high voltage.
  • Identify condition under which high voltage is always present and personal protection equipment (PPE) and proper procedures must be followed.

Before working on any high voltage system, be sure to wear the following Personal Protection Equipment:

  • Safety glasses with appropriate side shields when within 15 meters (50 feet) of the vehicle, either indoors or outdoors.
  • Certified and up-to-date Class "0" Insulation gloves rated at 1000V with leather protectors.
    • Visually and functionally inspect the gloves before use.
    • Wear the Insulation gloves with leather protectors at all times when working with the high voltage battery assembly, whether the system is energized or not.

Failure to follow the procedures may result in serious injury or death.

  1. Vehicle OFF, disconnect the X1 harness connector at the B305 Ambient Light/Sunload Sensor and Battery State of Charge Indicator.
  2. Test for less than 10 Ω between the low reference terminal 1 and ground.
    • If 10 Ω or greater 

      Repair the open/high resistance in the circuit.

    • Go to next step: If less than 10 Ω 
    3. NOTE:

    If the drive motor battery charger cable is connected. The drive motor battery charger cable must be disconnected for more than 10 s before performing the next step.

  3. Connect a test lamp between the yellow LED control circuit terminal 4 and ground.
  4. Verify the test lamp does not illuminate.
    • If the test lamp illuminates 
    1. Disconnect the X2 harness connector at the K114B Hybrid/EV Powertrain Control Module 2.
    2. Test for less than 1 V between the control circuit and ground.
      • If 1 V or greater, repair the short to voltage in the circuit.
      • If less than 1 V, replace the K114B Hybrid/EV Powertrain Control Module 2.
    • Go to next step: If the test lamp does not illuminate 
  5. Connect the drive motor battery charger cable.
  6. Verify that the test lamp illuminates or flashes in the first 5 s of connecting the drive motor battery charger cable.
    • If the test lamp does not illuminate 
    1. Disconnect the X2 harness connector at the K114B Hybrid/EV Powertrain Control Module 2.
    2. Test for infinite resistance between the control circuit and ground
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K114B Hybrid/EV Powertrain Control Module 2.
    • Go to next step: If the test lamp illuminates 
  7. Disconnect the drive motor battery charger cable for at least 10 s. Connect a test lamp between the green LED control circuit terminal 3 and ground.
  8. Verify test lamp does not illuminate.
    • If the test lamp illuminates 
    1. Disconnect the X2 harness connector at the K114B Hybrid/EV Powertrain Control Module 2.
    2. Test for less than 1 V between the control circuit and ground.
      • If 1 V or greater, repair the short to voltage in the circuit.
      • If less than 1 V, replace the K114B Hybrid/EV Powertrain Control Module 2.
    • Go to next step: If the test lamp does not illuminate 
  9. Connect the drive motor battery charger cable.
  10. Verify that the test lamp illuminates or flashes within 25 s of connecting the drive motor battery charger cable.
    • If the test lamp does not illuminate 
    1. Disconnect the X2 harness connector at the K114B Hybrid/EV Powertrain Control Module 2.
    2. Test for infinite resistance between the control circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • Go to next step: If infinite resistance
    3. Test for less than 2 Ω in the control circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K114B Hybrid/EV Powertrain Control Module 2.
    • Go to next step: If the test lamp illuminates 
  11. Replace the B305 Ambient Light/Sunload Sensor and Battery State of Charge Indicator.
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