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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 and connector end views to identify the device's 5 V reference, high voltage fault signal, low reference, and serial data circuit terminals.

  1. Perform the High Voltage Disabling procedure before proceeding with this diagnostic. 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 X1 harness connector at the K112B Hybrid/EV Battery Interface Control Module 2. It may take up to 2 min for all vehicle systems to power down.
  4. Test for less than 10 Ω between the low reference circuit terminal 12 X1 and ground.
    • If 10 Ω or greater 
    1. Vehicle OFF, disconnect the X1 harness connector at the K112A Hybrid/EV Battery Interface Control Module 1.
    2. Test for less than 2 Ω in the low reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K112A Hybrid/EV Battery Interface Control Module 1.
    • If less than 10 Ω 
  5. Vehicle in Service Mode.
  6. Test for 4.8-5.2 V between the 5 V reference circuit terminal 9 X1 and ground.
    • If less than 4.8 V 
    1. Vehicle OFF, disconnect the X1 harness connector at the K112A Hybrid/EV Battery Interface Control Module 1.
    2. Test for infinite resistance between the 5 V reference circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the 5 V reference circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K112A Hybrid/EV Battery Interface Control Module 1.
    • If greater than 5.2 V 
    1. Vehicle OFF, disconnect the X1 harness connector at the K112A Hybrid/EV Battery Interface Control Module 1, Vehicle in Service Mode.
    2. Test for less than 1 V between the 5 V reference circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K112A Hybrid/EV Battery Interface Control Module 1.
    • If between 4.8-5.2 V 
  7. Vehicle in Service Mode.
  8. Test for 4.8-5.2 V between the high voltage fault signal circuit terminal 13 X1 and ground.
    • If less than 4.8 V 
    1. Vehicle OFF, disconnect the X1 harness connector at the K112A Hybrid/EV Battery Interface Control Module 1.
    2. Test for infinite resistance between the high voltage fault signal circuit and ground.
      • If less than infinite resistance, repair the short to ground on the circuit.
      • If infinite resistance
    3. Test for less than 2 Ω in the high voltage fault signal circuit end to end.
      • If 2 Ω or greater, repair the open/high resistance in the circuit.
      • If less than 2 Ω, replace the K112A Hybrid/EV Battery Interface Control Module 1.
    • If greater than 5.2 V 
    1. Vehicle OFF, disconnect the X1 harness connector at the K112A Hybrid/EV Battery Interface Control Module 1, Vehicle in Service Mode.
    2. Test for less than 1 V between the high voltage fault signal circuit and ground.
      • If 1 V or greater, repair the short to voltage on the circuit.
      • If less than 1 V, replace the K112A Hybrid/EV Battery Interface Control Module 1.
    • If between 4.8-5.2 V 
  9. 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 X1 harness connector at the K112A Hybrid/EV Battery Interface Control Module 1. It may take up to 2 min for all vehicle systems to power down.
  10. Test for less than 2 Ω in each serial data circuit between the K112B Hybrid/EV Battery Interface Control Module 2 and K112A Hybrid/EV Battery Interface Control Module 1:
    • K112B Hybrid/EV Battery Interface Control Module 2 terminal 10 X1 and K112A Hybrid/EV Battery Interface Control Module 1 terminal 17 X1
    • K112B Hybrid/EV Battery Interface Control Module 2 terminal 11 X1 and K112A Hybrid/EV Battery Interface Control Module 1 terminal 16 X1
    • If 2 Ω or greater 

      Repair the open/high resistance in the serial data circuit.

    • If less than 2 Ω 
    11. NOTE:

    The K112B Hybrid/EV Battery Interface Control Module 2 has a loop in the harness that connects its 5 V reference circuit terminal 19 X1 to its signal ground circuit terminal 6 X1. Test this circuit for the appropriate failure mode short to voltage, short to ground, or open/high resistance prior to replacing the K112B Hybrid/EV Battery Interface Control Module 2.

  11. Replace the K112B Hybrid/EV Battery Interface Control Module 2.
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