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P0B7E




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 (with HP2) (Initial Inspection and Diagnostic Overview)Diagnostic System Check - Vehicle (without HP2) (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) 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

Diagnostic Fault Information





Typical Scan Tool Data





Circuit/System Description

The drive motor generator battery control module is also referred to as the battery energy control module (BECM). The BECM will diagnose its own systems and determine when a fault condition is present. Diagnostics and system status is communicated from the BECM to the hybrid powertrain control module (HPCM) through serial data. The HPCM is the host controller for diagnostic trouble code (DTC) information.

The hybrid battery assembly consists of 40 individual batteries. Each battery is rated at 7.2 V. The batteries are connected together in a series circuit. The BECM monitors the hybrid battery voltage on every two batteries for a total of 20 locations, across the battery assembly. If a hybrid battery voltage measurement drops below a calibrated value, this DTC will set.

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 voltage values are less than 7.5 V for 1.5 seconds.

P0B9C

The hybrid battery 20 voltage is less than 7.5 V for 1.5 seconds.

Action Taken When the DTC Sets

* The BECM commands the battery vent fan to high speed.
* If more than 4 of these DTCs are set, the drive motor generator battery sends a message to the HPCM 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 (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions (Diagnostic Trouble Code Descriptions)
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 13-19 Volts.

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.


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. Remove the drive motor generator battery upper cover. Refer to Drive Motor Battery Case Upper Cover, Front Cover, and Right Side Cover Replacement (Drive Motor Battery Case Upper Cover, Front Cover, and Right Side Cover Replacement).
3. Disconnect the X4 harness connector at the BECM.
4. Connect the EL-48571 high voltage battery pin out box to the X4 harness connector.
5. Install the high voltage manual disconnect lever.
6. Test for 13-19 volts across all 20 battery voltage reference circuits.

• 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 (Drive Motor Generator Battery Replacement)
* Control Module References (Programming and Relearning) - for drive motor generator battery control module replacement, setup and programming.

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