Circuit/System Testing

WARNING: This page is about a different variant/trim than selected.

Vehicle OFF, disable the high voltage at the A4 Hybrid/EV Battery Pack. Refer to High Voltage Disabling .
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.
Remove the A4 hybrid/EV battery pack cover. Refer to High Voltage Battery Cover Replacement .
Disconnect the X4 harness connector at the A28 Hybrid/EV Battery Contactor Assembly.
Test for between 170 k and 240 k between the ground circuit terminal 4, X4 and ground.
- If not within the specified range
1. Disconnect the X4 harness connector at the K114B Hybrid Powertrain Control Module 2.
2. Test for less than 2 Ω in the ground circuit end to end.
  - If 2 Ω or greater, repair the open/high resistance in the circuit.
  - If less than 2 Ω, repair the open/high resistance in the ground connection.
- If less than 10 Ω
Connect the 12V battery. Vehicle in Service Mode.
NOTE: Connecting the 12V battery with the S15 manual service disconnect removed may set other DTCs.
Verify that a test lamp does not illuminate between each A28 Hybrid/EV Battery Contactor Assembly harness connector control circuit terminals listed below and ground:
- Terminal 1 X4
- Terminal 2 X4
- Terminal 3 X4
- If the test lamp illuminates on any circuit
1. Vehicle OFF, disconnect the X4 harness connector at the K114B Hybrid Powertrain Control Module 2. Vehicle in Service Mode.
2. Test for less than 1 V between the control circuit and ground.
  - If 1 V or greater, repair the short to voltage on the circuit.
  - If less than 1 V, replace the K114B Hybrid Powertrain Control Module 2.
- If the test lamp does not illuminate on all circuits
Vehicle OFF, disconnect the X4 harness connector at the K114B Hybrid Powertrain Control Module 2.
Test for infinite resistance between each A28 Hybrid/EV Battery Contactor Assembly harness connector control circuit terminals listed below and ground:
- Terminal 1 X4
- Terminal 2 X4
- Terminal 3 X4
- If less than infinite resistance on either circuit
  Repair the short to ground on the circuit.
- If infinite resistance on both circuits
Test for less than 2 Ω between the harness connector terminals listed below:
- Terminal 1 X4 at the A28 Hybrid/EV Battery Contactor Assembly and terminal 3 X4 at the K114B Hybrid Powertrain Control Module 2
- Terminal 2 X4 at the A28 Hybrid/EV Battery Contactor Assembly and terminal 2 X4 at the K114B Hybrid Powertrain Control Module 2
- Terminal 3 X4 at the A28 Hybrid/EV Battery Contactor Assembly and terminal 1 X4 at the K114B Hybrid Powertrain Control Module 2
- If 2 Ω or greater on any circuit
  Repair the open/high resistance in the circuit.
- If less than 2 Ω on all circuits
Replace the A28 Hybrid/EV Battery Contactor Assembly.
Verify the DTC does not set while operating the vehicle within the Conditions for Running the DTC.
- If the DTC sets
  Replace the K114B Hybrid Powertrain Control Module 2.
- If the DTC does not set
All OK.