Circuit/System Testing
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.
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.
- Ignition OFF, disable high voltage at the A4 Hybrid/EV Battery Pack. Refer to High Voltage Disabling .
- Connect the X1, X2, and X3 harness connectors at the K59 Starter/Generator Control Module.
- Verify DTC P0ADB, P0ADC, P0AE6, or P0AE7 is not set.
- If any of the DTCs are set
Refer to Diagnostic Trouble Code (DTC) List - Vehicle .
- If none of the DTCs are set
- If any of the DTCs are set
- Remove the KR38 Main Contactor, KR134 Pre-Charge Contactor, and the S15 Manual Service Disconnect from the A4 Hybrid/EV Battery Pack.
- Install a 10 A fused jumper wire between the KR38 Main Contactor B+ terminal 1 X1 and 12 V. Install a jumper wire between the KR38 Main Contactor control terminal 2 X1 and ground.
- Test for less than 10 Ω between the high voltage terminals at the KR38 Main Contactor.
- If 10 Ω or greater
The KR38 Main Contactor is stuck in the open position. Replace the KR38 Main Contactor.
- If less than 10 Ω
- If 10 Ω or greater
- Install a 10 A fused jumper wire between the KR134 Pre-Charge Contactor B+ terminal A X1 and 12 V. Install a jumper wire between the KR134 Pre-Charge Contactor control terminal A X2 and ground.
- Test for less than 10 Ω between the high voltage terminals at the KR134 Pre-Charge Contactor.
- If 10 Ω or greater
The KR134 Pre-Charge Contactor is stuck in the open position. Replace the KR134 Pre-Charge Contactor.
- If less than 10 Ω
- If 10 Ω or greater
- Test for less than 10 Ω between the high voltage terminals at the S15 Manual Service Disconnect with the lever in the closed position.
- If 10 Ω or greater
The S15 Manual Service Disconnect is stuck in the open position. Replace the S15 Manual Service Disconnect.
- If less than 10 Ω
- If 10 Ω or greater
- Replace the K59 Starter/Generator Control Module.
In High Voltage Disabling , perform the disabling procedure for servicing components within the energy storage system. The C4A Hybrid/EV Battery Section 1 and C4B Hybrid/EV Battery Section 2 will be disconnected as part of the disabling procedure.
The following steps will test the KR38 Main Contactor, KR134 Pre-Charge Contactor, and the S15 Manual Service Disconnect as a type of component test. These components must be removed from the A4 Hybrid/EV Battery Pack to ensure proper test results.