P0ADB
DTC P0ADB or P0ADC
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptor
DTC P0ADB
- Hybrid Battery Positive Contactor Control Circuit Low Voltage
DTC P0ADC
- Hybrid Battery Positive Contactor Control Circuit High Voltage
Circuit/System Description
The hybrid battery system voltage is controlled by two high voltage contactors. The high voltage contactors allow the high voltage DC batteries to be connected to the vehicle or safely contain the high voltage DC within the hybrid battery pack assembly. Of the two contactors, one is a pre-charge contactor and the other is the primary contactor. The two contactors are closed in a specific sequence by the starter/generator control module. The pre-charge contactor is closed first. This causes high voltage to flow through the pre-charge resistor, allowing system voltage to build slowly. Once the system voltage has raised and stabilized, the primary contactor is closed. Both contactors are controlled by the starter/generator control module. The starter/generator control module supplies B+ to each contactor at all times. When the contactors are to be closed, the starter/generator control module will provide a groupd to the contactor through a low side driver.
Conditions for Running the DTC
The 12 V battery voltage is greater than 6.0 V
Conditions for Setting the DTC
P0ADB
* An open is detected on the primary contactor control circuit when the contactor control is commanded ON and measured resistance is greater than 200K ohm
* A short to voltage is detected on the primary contactor control circuit when the contactor control is commanded ON and current sense feedback is less than 0.5 A
P0ADC
A short to ground is detected on the primary contactor control circuit when the contactor control is commanded OFF and current sense feedback is less than 0.5 A
Action Taken When the DTC Sets
DTCs P0ADB and P0ADC are type B DTCs
Conditions for Clearing the DTC
DTCs P0ADB and P0ADC are type B DTCs
Reference Information
Schematic Reference
Hybrid Energy Storage Schematics [1][2]Electrical Diagrams
Connector End View Reference
Component Connector End Views Connector End Views By Name
Description and Operation
Drive Motor Battery System Description Drive Motor Battery System Description
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
DTC Type Reference
Powertrain Diagnostic Trouble Code (DTC) Type Definitions Powertrain Diagnostic Trouble Code (DTC) Type Definitions
Scan Tool Reference
Control Module References Control Module References for scan tool information
Special Tools
EL-48900 - HEV Safety Kit
For equivalent regional tools, refer to Special Tools Tools and Equipment.
Circuit/System Verification
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: The eAssist battery pack assembly will utilize an exchange program. Please consult the most recent revision of bulletin/PI #PIPXXYYZZ, 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, disable high voltage at the A4 hybrid/EV battery pack. Refer to High Voltage Disabling High Voltage Disabling.
2. Disconnect the X1 harness connector at the KR38 main contactor.
3. Connect the 12 V battery.
4. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal 1.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K59 starter/generator control module.
5. Test for less than 1 V between the control circuit terminal 2 and ground.
• If greater than the specified range, test the control circuit for a short to voltage.
6. Ignition OFF, connect the harness connector at the KR38 main contactor. Disconnect the X4 harness connector at the K59 starter/generator control module.
7. Test for infinite resistance between the control circuit terminal 5 and ground.
• If less than the specified value, test the control circuit for a short to ground.
8. Test for 20-40 ohm between the B+ circuit terminal 4 and the control circuit terminal 5.
• If not within the specifide range, test the control circuit for an open/high resistance. If the circuit tests normal, test or replace the KR38 main contactor.
9. If all circuits test normal, replace the K59 starter/generator control module.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
Control Module References Control Module References