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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. Clear DTC, connect a KNOWN GOOD drive motor battery charger cable to vehicle.
  2. Verify DTC P1EE6 is set.
    • If DTC P1EE6 is not set 
    1. If possible, attempt to charge with the customer's drive motor battery charger cable.
    2. Verify DTC P1EE6 is set.
      • If DTC P1EE6 is set, replace the customers drive motor battery charger cable.
      • If DTC P1EE6 is not set, Vehicle OK. Advise the customer to have their electrical service provider inspect the household power outlet for insufficient voltage, high frequency noise, or open/high resistance.
    • Go to next step: If DTC P1EE6 is set 
  3. Vehicle OFF, disable the high voltage at the T18 Battery Charger. Refer to High Voltage Disabling
  4. Disconnect the X2 harness connector at the T18 Battery Charger.
  5. Verify that all HV harness connector and the mating module connector terminals are free from moisture, corrosion, and arc flash damage.
    • If any terminals show signs of damage 

      Replace the HV wiring harness and affected modules as necessary.

    • Go to next step: If no arc flash damage, moisture, or corrosion is found 
  6. Test into the harness for infinite resistance between the AC circuit terminals listed below and ground:
    • T18 Battery Charger terminal 1 X2
    • T18 Battery Charger terminal 4 X2
    • If less than infinite resistance 
    1. Disconnect the harness connector to the X98 Hybrid/EV Battery Charger Receptacle.
    2. Verify that all HV harness connector and the mating module connector terminals are free from moisture, corrosion, and arc flash damage.
      • If any terminals show signs of damage, replace the HV wiring harness and affected modules as necessary.
      • Go to next step: If no arc flash damage, moisture, or corrosion is found
    3. Test into the harness for infinite resistance between the appropriate AC circuit terminal and ground.
      • If less than infinite resistance, replace the high voltage wiring harness.
      • If infinite resistance, replace the X98 Hybrid/EV Battery Charger Receptacle.
    • Go to next step: If infinite resistance 
  7. Test into the harness for infinite resistance between all the AC circuit terminals listed below:
    • T18 Battery Charger terminal 1 X2
    • T18 Battery Charger terminal 3 X2
    • T18 Battery Charger terminal 4 X2
    • If less than infinite resistance 
    1. Disconnect the harness connector to the X98 Hybrid/EV Battery Charger Receptacle.
    2. Verify that all HV harness connector and the mating module connector terminals are free from moisture, corrosion, and arc flash damage.
      • If any terminals show signs of damage, replace the HV wiring harness and affected modules as necessary.
      • Go to next step: If no arc flash damage, moisture, or corrosion is found
    3. Test into the harness for infinite resistance between the three AC circuit terminals.
      • If less than infinite resistance, replace the high voltage wiring harness.
      • If infinite resistance, replace the X98 Hybrid/EV Battery Charger Receptacle.
    • Go to next step: If infinite resistance 
  8. GM4177681Courtesy of GENERAL MOTORS COMPANY

    Test for less than 10 Ω between the AC circuit terminals listed below:

    • T18 Battery Charger terminal 1 X2 and X98 Hybrid/EV Battery Charger Receptacle face 3
    • T18 Battery Charger terminal 3 X2 and X98 Hybrid/EV Battery Charger Receptacle face 1
    • T18 Battery Charger terminal 4 X2 and X98 Hybrid/EV Battery Charger Receptacle face 4
    • If 10 Ω or greater 
    1. Disconnect the harness connector to the X98 Hybrid/EV Battery Charger Receptacle.
    2. Verify that all HV harness connector and the mating module connector terminals are free from moisture, corrosion, and arc flash damage.
      • If any terminals show signs of damage, replace the HV wiring harness and affected modules as necessary.
      • Go to next step: If no arc flash damage, moisture, or corrosion is found
    3. Test for less than 2 Ω between the AC circuit terminals listed below:
      • X98 Hybrid/EV Battery Charger Receptacle inline 3 and X98 Hybrid/EV Battery Charger Receptacle face 3
      • X98 Hybrid/EV Battery Charger Receptacle inline 4 and X98 Hybrid/EV Battery Charger Receptacle face 4
      • If 2 Ω or greater, replace the X98 Hybrid/EV Battery Charger Receptacle and the T18 Battery Charger.
      • If less than 2 Ω, replace the high voltage wiring harness.
    • Go to next step: If less than 10 Ω 
  9. Replace the T18 Battery Charger.
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