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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.

NOTE:

Use the schematics to determine which devices are on the K114B Hybrid/EV Powertrain Control Module 2 terminal 48 X2 high voltage energy management communication enable circuit. Use the connector end views to identify the B+, ignition, and high voltage energy management communication enable circuit terminals for each of those devices.

  1. Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 m (9.8 ft) away from vehicle. Disconnect the X2 harness connector at the K114B Hybrid/EV Powertrain Control Module 2. It may take up to 2 min for all vehicle systems to power down.
  2. Test for greater than 100 Ω, but less than infinite resistance, between the high voltage energy management communication enable circuit terminal 48 X2 and ground.
    • If 100 Ω or less 

      Refer to Testing the High Voltage Energy Management Communication Enable Circuits for a Short to Ground.

    • If infinite resistance 

      Test for an open/high resistance in the high voltage energy management communication enable circuit.

    • Go to next step: If greater than 100 Ω and less than infinite resistance 
  3. Vehicle in Service Mode.
  4. Verify that a test lamp illuminates between each B+ circuit terminal and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Vehicle OFF.
    2. Test for less than 2 Ω in the B+ circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, verify the fuse is not open and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Vehicle OFF.
    2. Test for infinite resistance between the B+ circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K114B Hybrid/EV Powertrain Control Module 2.
    • Go to next step: If the test lamp illuminates 
  5. Vehicle in Service Mode.
  6. Verify that a test lamp illuminates between each ignition circuit terminal and ground.
    • If the test lamp does not illuminate and the circuit fuse is good 
    1. Vehicle OFF.
    2. Test for less than 2 Ω in the ignition circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, verify the fuse is OK and there is voltage at the fuse.
    • If the test lamp does not illuminate and the circuit fuse is open 
    1. Vehicle OFF.
    2. Test for infinite resistance between the ignition circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance, replace the K114B Hybrid/EV Powertrain Control Module 2.
    • Go to next step: If the test lamp illuminates 
  7. Replace the K114B Hybrid/EV Powertrain Control Module 2.

Testing the High Voltage Energy Management Communication Enable Circuits for a Short to Ground

  1. Perform the High Voltage Disabling procedure. Refer to High Voltage Disabling .
  2. Reconnect the 12 V battery.
  3. Vehicle OFF, all access doors closed, all vehicle systems OFF, and all keys at least 3 m (9.8 ft) away from vehicle. Disconnect the harness connector at an easily accessible device that shares the K114B Hybrid/EV Powertrain Control Module 2 terminal 48 X2 high voltage energy management communication enable circuit. It may take up to 2 min for all vehicle systems to power down.
  4. Test for less than 100 Ω between the K114B Hybrid/EV Powertrain Control Module 2 high voltage energy management communication enable circuit terminal 48 X2 and ground.
    • If 100 Ω or greater 

      Replace the device that was just disconnected.

    • Go to next step: If less than 100 Ω 
  5. Repeat step 3 until all devices on the K114B Hybrid/EV Powertrain Control Module 2 high voltage energy management communication enable circuit terminal 48 X2 have been disconnected.
  6. Repair the short to ground on the high voltage energy management communication enable circuit.
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