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 will perform the following tasks:

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 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 at all times when working with the high voltage battery assembly, whether the system is energized or not.

Failure to follow the procedures exactly as written may result in serious injury or death.

WARNING: The Volt Battery Pack will utilize an exchange program. Please consult the most recent revision of bulletin/PI #PIP4841, available in Service Information (SI), for a list of approved Volt Battery Pack service procedures. Components that may be removed and serviced without exchanging the complete battery pack are identified in the bulletin/PI. Please contact the GM Technical Assistance Center (1-877-446-8227) if you have any questions.

WARNING: This diagnostic has NOT been validated on-vehicle. Follow all safety protocol and utilize all appropriate personal protective equipment to ensure your safety. Failure to follow the procedures exactly as written may result in serious injury or death.

NOTE: Use the schematic to identify the control modules B+, ignition, ground, communication enable and serial data circuit terminals.

Ignition OFF, disconnect the X1 harness connector at the A4 hybrid battery pack.
Ignition ON, verify that a test lamp illuminates between the high voltage energy management communication enable circuit terminal 5 X1 and ground.
- If the test lamp does not illuminate, test the circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the K114B hybrid powertrain control module 2.
Ignition OFF and all vehicle systems OFF, key out of the ignition switch, all access doors closed. It may take up to 2 minutes for all vehicle systems to power down. Verify that a test lamp does not illuminate between the high voltage energy management communication enable circuit terminal 5 X1 and ground.
- If the test lamp illuminates, test the circuit for a short to voltage. If the circuit tests normal, replace the K114B hybrid powertrain control module 2.
Ignition OFF, connect the X1 harness connector at the A4 hybrid battery pack.
Perform the High Voltage Disabling procedure before proceeding with this diagnostic. Refer to High Voltage Disabling .
Reconnect the 12 V battery.
Ignition OFF, disconnect the X1 harness connector at the K16 battery energy control module.
Ignition ON, verify that a test lamp illuminates between the high voltage energy communication enable circuit terminal 16 X1 and ground.
- If the test lamp does not illuminate, test the circuit for a short to ground or open/high resistance. If the circuit tests normal, replace the drive motor battery wire junction block relay.
Ignition OFF and all vehicle systems OFF, key out of the ignition switch, all access doors closed. It may take up to 2 minutes for all vehicle systems to power down. Verify that a test lamp does not illuminate between the high voltage energy communication enable circuit terminal 16 X1 and ground.
- If the test lamp illuminates, test the circuit for a short to voltage. If the circuit tests normal, replace the drive motor battery wire junction block relay.
If all circuits test normal, replace the K16 battery energy control module.