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Circuit/System Verification

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.

WARNING:

Before working internally on the high voltage battery, be sure to wear Personal Protection Equipment (PPE) in accordance with National Fire Protection Association (NFPA) 70E, PPE Category 2, Minimum Arc Rating 8 cal/cm 2:

  • Safety face shield and sock hood/balaclava
  • Safety rated long sleeve shirt and pants or safety rated coveralls.
  • Hearing protection
  • 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 these precautions could result in serious personal injury or death.
  1. Verify a low 12 battery event did not occur.

    Inspect for DTC P0562 or similar. Refer to Diagnostic Trouble Code (DTC) List - Vehicle .

    • If a low 12 V battery condition occurred 

      Repair the cause of the low 12 V battery.

    • Go to next step: If a low 12 V battery condition did not occur 
  2. Record the freeze frame/failure records for DTC P0C76.
  3. Vehicle ON.
  4. With a scan tool, clear DTC information.
  5. NOTE:

    To ensure the DTC has cleared you must get propulsion ready as this DTC normally sets during vehicle OFF power down.

  6. Vehicle ON, propulsion/vehicle ready. Vehicle OFF and wait 12 minutes. Vehicle ON, propulsion/vehicle ready. Vehicle OFF and wait 12 minutes. Vehicle ON, Verify DTC P0C76 is not set.
    • If the DTC is set 

      Disable the high voltage and replace the A28 Hybrid/Electric Vehicle Battery Contactor Assembly.

    • Go to next step: If the DTC is not set 
  7. All OK.