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.

Vehicle OFF, disable the high voltage. Refer to High Voltage Disabling . Disconnect the X2 connector at the A4 Hybrid/EV Battery Pack.

NOTE:

The following continuity tests must be performed using the EL-50772 Insulation Multimeter. Select the Isolation test setting, then select the 500 V range.

Using the EL-50772 Insulation Multimeter test for greater than 1M Ω between the circuit terminals listed below and ground;
- Terminal A X2
- Terminal B X2
- If less than 1M Ω
1. Disconnect the X4 connector at the T18 Battery Charger.
2. Using the EL-50772 Insulation Multimeter test the circuit for greater than 1M Ω between the circuit terminal and ground.
  - If less than 1M Ω, test or replace the Hybrid/EV Battery Pack Coolant Heater Fuse and replace the high voltage DC cables.
  - If 1M Ω or greater, test or replace the Hybrid/EV Battery Pack Coolant Heater Fuse and replace the T18 Battery Charger.
- If 1M Ω or greater
Test for greater than 1M Ω between the harness connector terminal A and terminal B X5.
- If less than 1M Ω
1. Disconnect the X4 connector at the T18 Battery Charger.
2. Test for greater than 1M Ω between the A4 Hybrid/EV Battery Pack terminal A and terminal B X5.
  - If less than 1M Ω, test or replace the Hybrid/EV Battery Pack Coolant Heater Fuse and replace the high voltage DC cables.
  - If 1M Ω or greater, test or replace the Hybrid/EV Battery Pack Coolant Heater Fuse and replace the T18 Battery Charger.
- If 1M Ω or greater
Disconnect the X4 connector at the T18 Battery Charger.

NOTE:

The following continuity test must be performed using the Ohm test setting.

Test for less than 10 Ω between the high voltage circuit terminals listed below;
- Terminal A X4 and terminal A X5
- Terminal B X4 and terminal B X5
- If 10 Ω or greater
  Test or replace the Hybrid/EV Battery Pack Coolant Heater Fuse and replace the high voltage DC cables.
- If less than 10 Ω
Replace the T18 Battery Charger.
Verify that DTC P0D21, P0D22 or P0D23 does not set while operating the vehicle within the Conditions for Running the DTC.
- If any of the DTCs set
  Replace the K114B Hybrid Powertrain Control Module 2.
- If none of the DTCs set
All OK.