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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. Disable the high voltage for every high voltage component. High Voltage Disabling .
  2. With high voltage disabled, identify the A4 Hybrid/Electric Vehicle Battery Pack high voltage connector X5 and disconnect; if the X5 connector has not been disconnected. High Voltage Disabling .
    3. NOTE:

    This step assumes the high voltage connector is still connected to the T12EF front electric drive transmission module.

  3. Measure the resistance between A4 Hybrid/Electric Vehicle Battery Pack connector X5 terminals 1 and 2, on the harness side.
    • If less than infinite resistance 
    • A4 Hybrid/EV Battery Pack - Replace
    • Go to next step: If infinite resistance 
  4. Remove the necessary component to gain access to the T12EF Front Electric Drive Transmission Module high voltage connector X2.
  5. Disconnect X2 and inspect the high voltage Battery Positive and Negative Cable and terminals for damage.
    • If damage is found 
    • Replace the high voltage Battery Positive and Negative Cable.
    • Go to next step: If no damage is found 
  6. Test the high voltage cable for an open condition.
    • If infinite resistance 
    • Replace the high voltage Battery Positive and Negative Cable.
    • Go to next step: If less than infinite resistance 
  7. K107A Drive Motor 1 Control Module - Replace
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