P0B4C
DTC P0B3D, P0B42, P0B47, P0B4C, P0B51, P0B56, P0B5B, P0B60, P0B65, P0B6A, P0B6F, P0B74, P0B79, P0B7E, P0B83, P0B88, P0B8D, P0B92, P0B97, or P0B9C
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 Descriptors
DTC P0B3D
- Hybrid Battery 1 Circuit Low Voltage
DTC P0B42
- Hybrid Battery 2 Circuit Low Voltage
DTC P0B47
- Hybrid Battery 3 Circuit Low Voltage
DTC P0B4C
- Hybrid Battery 4 Circuit Low Voltage
DTC P0B51
- Hybrid Battery 5 Circuit Low Voltage
DTC P0B56
- Hybrid Battery 6 Circuit Low Voltage
DTC P0B5B
- Hybrid Battery 7 Circuit Low Voltage
DTC P0B60
- Hybrid Battery 8 Circuit Low Voltage
DTC P0B65
- Hybrid Battery 9 Circuit Low Voltage
DTC P0B6A
- Hybrid Battery 10 Circuit Low Voltage
DTC P0B6F
- Hybrid Battery 11 Circuit Low Voltage
DTC P0B74
- Hybrid Battery 12 Circuit Low Voltage
DTC P0B79
- Hybrid Battery 13 Circuit Low Voltage
DTC P0B7E
- Hybrid Battery 14 Circuit Low Voltage
DTC P0B83
- Hybrid Battery 15 Circuit Low Voltage
DTC P0B88
- Hybrid Battery 16 Circuit Low Voltage
DTC P0B8D
- Hybrid Battery 17 Circuit Low Voltage
DTC P0B92
- Hybrid Battery 18 Circuit Low Voltage
DTC P0B97
- Hybrid Battery 19 Circuit Low Voltage
DTC P0B9C
- Hybrid Battery 20 Circuit Low Voltage
Circuit/System Description
The system contains twenty battery modules. Each module contains two 7.2 V cells for a total nominal system voltage of 288 V. Each battery module is rated at 14.4 V direct current (DC) and all the modules are connected together in series. The drive motor generator battery is also referred to as the hybrid battery. The drive motor generator battery control module is also referred to as the battery energy control module (BECM). The drive motor generator battery control module monitors the hybrid battery voltage on the twenty battery modules. The drive motor generator battery control module determines the actual terminal voltage by monitoring the output voltage from the high voltage contactors.
The drive motor generator battery control module will diagnose its own systems and determine when a fault condition is present. Diagnostics and system status is communicated from the drive motor generator battery control module to the hybrid powertrain control module (HPCM) through serial data. The hybrid powertrain control module is the host controller for diagnostic trouble code (DTC) information.
Conditions for Running the DTC
* DTC P0A1F is not set.
* The ignition is ON.
* The 12 V battery voltage is 9-18 V.
Conditions for Setting the DTC
P0B3D, P0B42, P0B47, P0B4C, P0B51, P0B56, P0B5B, P0B60, P0B65, P0B6A, P0B6F, P0B74, P0B79, P0B7E, P0B83, P0B88, P0B8D, P0B92, and P0B97
Any two consecutive hybrid battery voltages are less than 7.5 V for 1.5 seconds.
P0B9C
Hybrid battery number 20 voltage is less than 7.5 V for 1.5 seconds. DTC P0B9C only requires one voltage failure because battery 20 is the last battery.
Action Taken When the DTC Sets
* DTCs P0B3D, P0B42, P0B47, P0B4C, P0B51, P0B56, P0B5B, P0B60, P0B65, P0B6A, P0B6F, P0B74, P0B79, P0B7E, P0B83, P0B88, P0B8D, P0B92, P0B97, and P0B9C are type B DTCs.
* The drive motor generator battery control module commands the battery vent fan to high speed.
* If more than 4 of these DTCs are set, the drive motor generator battery control module sends a message to the hybrid powertrain control module to reduce the power use limit to 50 percent.
Conditions for Clearing the DTC
DTCs P0B3D, P0B42, P0B47, P0B4C, P0B51, P0B56, P0B5B, P0B60, P0B65, P0B6A, P0B6F, P0B74, P0B79, P0B7E, P0B83, P0B88, P0B8D, P0B92, P0B97, and P0B9C are type B DTCs.
Reference Information
Schematic Reference
Hybrid Energy Storage Schematics (Electrical Diagrams)
Connector End View Reference
Component Connector End Views (Connector Views)
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 (Programming and Relearning) for scan tool information
Special Tools
* EL-48571 High Voltage Battery Pin Out Box
* EL-48900 HEV Safety Kit
Circuit/System Verification
Ignition ON, observe the scan tool Hybrid Battery 1-20 parameters. Each reading should be between 10-19 V, and all readings should be within 1.5 V of each other.
Circuit/System Testing
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 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.
1. Ignition OFF, disable the high voltage at the drive motor generator battery. Refer to High Voltage Disabling (High Voltage Disabling).
2. Disconnect the X4 harness connector at the drive motor battery control module.
3. Connect the EL-48571 high voltage battery pin out box.
4. Install the high voltage manual disconnect lever. Measure and record each of the 20 battery voltages.
5. Each battery voltage reading should be between 10-19 V.
• If not within the specified range, replace the drive motor battery assembly.
6. Each battery voltage reading should be within 1.5 V of each other.
• If not within the specified range, replace the drive motor battery assembly.
7. If all circuits test normal, replace the drive motor generator battery control module.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the repair.
* Drive Motor Generator Battery Replacement and Shipping Preparation (Drive Motor Generator Battery Replacement and Shipping Preparation)
* Control Module References (Programming and Relearning) for drive motor generator battery control module replacement, setup and programming