High Voltage System Inspection
High Voltage System Inspection
A complete inspection of the high voltage system and components must be performed if the vehicle has been involved in a collision.
Vehicle Collision Detection
The Supplemental Inflatable Restraint (SIR) sensors are designed to identify the severity of a collision and from what direction a collision has occurred. The SIR sensors typically detect collision conditions for occupant impact-protection reasons. The starter/generator control module will open the high voltage contactor relays and disable the vehicle whenever an SIR deployment occurs.
The supplemental inflatable restraint module transmits through serial data to the starter/generator control module whenever a sensor fault is detected or a collision event has been detected. The starter/generator control module will set a Crash Event Detected event and enter into a disable condition.
The Crash Event Detected condition will remain active until cleared by the starter/generator control module Clear Secured High Voltage DTCs output control function of the scan tool.
Special Tools
EL-48900 - HEV Safety Kit
For equivalent regional tools, refer to Special Tools Tools and Equipment.
Inspection Procedure
Danger:
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 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 exactly as written may result in serious injury or death.
Danger:
High voltage circuits should only be tested using a digital multimeter (DMM) and test leads with at least a CAT III rating, such as the J 39200-A Digital Multimeter. Failure to follow the procedures exactly as written may result in serious injury or death.
Danger:
The eAssist battery pack assembly will utilize an exchange program. Please consult the most recent revision of bulletin/PI# PIC5520, available in Service Information♦(SI), for a list of approved eAssist battery pack assembly service procedures. Components that may be removed and serviced without exchanging the complete battery pack assembly are identified in the bulletin/PI. Please contact the GM Technical Assistance Center (1-877-446-8227) if you have any questions.
1. Ignition OFF, perform a visual inspection of the following high voltage components listed. Remove any trim covers, carpet, or shields to gain access. DO NOT remove the metal A4 hybrid/EV battery pack cover. Inspect the assembly and verify there are no case cracks, dents, pinched, cut or frayed high voltage cables, low voltage cables, or other physical damage.
* A4 hybrid/EV battery pack
* A15 starter/generator
* G14 hybrid/EV battery pack cooling fan
* G14 hybrid/EV battery pack cooling fan inlet and outlet ducts for proper positioning to the A4 hybrid/EV battery pack. Refer to Drive Motor Battery Cooling Air Inlet Upper Duct Replacement Drive Motor Battery Cooling Air Inlet Upper Duct Replacement , Drive Motor Battery Cooling Blower Outlet Duct Replacement Drive Motor Battery Cooling Blower Outlet Duct Replacement , and Drive Motor Battery Cooling Air Outlet Duct Replacement Drive Motor Battery Cooling Air Outlet Duct Replacement for proper duct installation and routing.
* High voltage cables between the K59 starter/generator control module and the A15 starter/generator
• If any damage is found
Ignition OFF, disable high voltage at the A4 hybrid/EV battery pack. Refer to High Voltage Disabling High Voltage Disabling. If vehicle damage does not allow for access to the S15 hybrid/EV battery pack high voltage manual disconnect lever, disconnect the 12V battery and remove the damaged portion of the vehicle until the S15 hybrid/EV battery pack high voltage manual disconnect lever can be accessed and the High Voltage Disabling High Voltage Disabling procedure can be completed. Replace any components and cables that have been identified as damaged. Continue to step 2 after repairs have been completed.
• If no damage is found
2. Enable high voltage at the A4 hybrid/EV battery pack. Refer to High Voltage Enabling High Voltage Enabling.
3. Ignition ON.
4. Verify no DTCs are set.
• If any DTCs are set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.
• If no DTCs are set
5. Clear the Crash Event Detected disable condition after all damaged high voltage components have been replaced. Refer to Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.
6. Perform the required body repairs using the approved service procedures.