GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2009 🢒 Tahoe - 2WD 🢒 Driver Information and Entertainment 🢒 Cellular, Entertainment, and Navigation 🢒 DTC P0B3C, P0B41, P0B46, P0B4B, P0B50, P0B55, P0B5A, P0B5F, P0B64, P0B69, P0B6E, P0B73, P0B78, P0B7D, P0B82, P0B87, P0B8C, P0B91, P0B96, or P0B9B

Diagnostic Instructions
    • Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
    • Review Strategy Based Diagnosis for an overview of the diagnostic approach.
    •  Diagnostic Procedure Instructions provides an overview of each diagnostic category.

DTC Descriptors

DTC P0B3C: Hybrid Battery 1 Circuit Performance

DTC P0B41: Hybrid Battery 2 Circuit Performance

DTC P0B46: Hybrid Battery 3 Circuit Performance

DTC P0B4B: Hybrid Battery 4 Circuit Performance

DTC P0B50: Hybrid Battery 5 Circuit Performance

DTC P0B55: Hybrid Battery 6 Circuit Performance

DTC P0B5A: Hybrid Battery 7 Circuit Performance

DTC P0B5F: Hybrid Battery 8 Circuit Performance

DTC P0B64: Hybrid Battery 9 Circuit Performance

DTC P0B69: Hybrid Battery 10 Circuit Performance

DTC P0B6E: Hybrid Battery 11 Circuit Performance

DTC P0B73: Hybrid Battery 12 Circuit Performance

DTC P0B78: Hybrid Battery 13 Circuit Performance

DTC P0B7D: Hybrid Battery 14 Circuit Performance

DTC P0B82: Hybrid Battery 15 Circuit Performance

DTC P0B87: Hybrid Battery 16 Circuit Performance

DTC P0B8C: Hybrid Battery 17 Circuit Performance

DTC P0B91: Hybrid Battery 18 Circuit Performance

DTC P0B96: Hybrid Battery 19 Circuit Performance

DTC P0B9B: Hybrid Battery 20 Circuit Performance

Diagnostic Fault Information

Circuit

Short to Ground

Open/High Resistance

Short to Voltage

Signal Performance

Battery 1 Voltage

P1AE7

P0B3D, P1A1F

P0B3E, P1A4E

P0B3C, P0BBD

Battery 2 Voltage

P1AE7

P0B42, P1A1F

P0B43, P1A4E

P0B41, P0BBD

Battery 3 Voltage

P1AE7

P0B47, P1A1F

P0B48, P1A4E

P0B46, P0BBD

Battery 4 Voltage

P1AE7

P0B4C, P1A1F

P0B4D, P1A4E

P0B4B, P0BBD

Battery 5 Voltage

P1AE7

P0B51, P1A1F

P0B52, P1A4E

P0B50, P0BBD

Battery 6 Voltage

P1AE7

P0B56, P1A1F

P0B57, P1A4E

P0B55, P0BBD

Battery 7 Voltage

P1AE7

P0B5B, P1A1F

P0B5C, P1A4E

P0B5A, P0BBD

Battery 8 Voltage

P1AE7

P0B60, P1A1F

P0B61, P1A4E

P0B5F, P0BBD

Battery 9 Voltage

P1AE7

P0B65, P1A1F

P0B66, P1A4E

P0B64, P0BBD

Battery 10 Voltage

P1AE7

P0B6A, P1A1F

P0B6B, P1A4E

P0B69, P0BBD

Battery 11 Voltage

P1AE7

P0B6F, P1A1F

P0B70, P1A4E

P0B6E, P0BBD

Battery 12 Voltage

P1AE7

P0B74, P1A1F

P0B75, P1A4E

P0B73, P0BBD

Battery 13 Voltage

P1AE7

P0B79, P1A1F

P0B7A, P1A4E

P0B78, P0BBD

Battery 14 Voltage

P1AE7

P0B7E, P1A1F

P0B7F, P1A4E

P0B7D, P0BBD

Battery 15 Voltage

P1AE7

P0B83, P1A1F

P0B84, P1A4E

P0B82, P0BBD

Battery 16 Voltage

P1AE7

P0B88, P1A1F

P0B89, P1A4E

P0B87, P0BBD

Battery 17 Voltage

P1AE7

P0B8D, P1A1F

P0B8E, P1A4E

P0B8C, P0BBD

Battery 18 Voltage

P1AE7

P0B92, P1A1F

P0B93, P1A4E

P0B91, P0BBD

Battery 19 Voltage

P1AE7

P0B97, P1A1F

P0B98, P1A4E

P0B96, P0BBD

Battery 20 Voltage

P1AE7

P0B9C, P1A1F

P0B9D, P1A4E

P0B9B, P0BBD

Typical Scan Tool Data

Hybrid Battery 1-20

Circuit

Short to Ground

Open

Short to Voltage

Operating Conditions: Ignition ON

Parameter Normal Range: 13-19 Volts

Battery 1-20 Voltage

13-19 Volts

0 Volts

--

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 volts. 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. The BECM determines the actual terminal voltage by monitoring the output voltage from the high voltage contactor relays. The BECM also multiplies each individual battery voltage measurement by 20, and compares this calculation to the terminal voltage measurement.

Conditions for Running the DTC
    • The ignition is ON.
    • The 12 V battery voltage is 9-18 V.
    • HV contactor relays are closed.

Conditions for Setting the DTC

DTCs P0B3C, P0B41, P0B46, P0B4B, P0B50, P0B55, P0B5A, P0B5F, P0B64, P0B69, P0B6E, P0B73, P0B78, P0B7D, P0B82, P0B87, P0B8C, P0B91, P0B96

The voltage of any two consecutive batteries multiplied by 20 is 70 V greater than or less than the total pack voltage for 16 seconds.

DTC P0B9B

The voltage of battery 20 multiplied by 20 is 70 V greater than or less than the total pack voltage for 16 seconds. DTC P0B9B only requires one voltage failure because battery 20 is the last battery.

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.
    • DTCs P0B3C, P0B41, P0B46, P0B4B, P0B50, P0B55, P0B5A, P0B5F, P0B64, P0B69, P0B6E, P0B73, P0B78, P0B7D, P0B82, P0B87, P0B8C, P0B91, P0B96, and P0B9B are type B DTCs.

Conditions for Clearing the DTC

DTCs P0B3C, P0B41, P0B46, P0B4B, P0B50, P0B55, P0B5A, P0B5F, P0B64, P0B69, P0B6E, P0B73, P0B78, P0B7D, P0B82, P0B87, P0B8C, P0B91, P0B96, and P0B9B are type B DTCs.

Reference Information

Schematic Reference

Hybrid Energy Storage Schematics

Connector End View Reference

Component Connector End Views

Description and Operation

Drive Motor Battery System Description

Electrical Information Reference

    •  Circuit Testing
    •  Connector Repairs
    •  Testing for Intermittent Conditions and Poor Connections
    •  Wiring Repairs

DTC Type Reference

Powertrain Diagnostic Trouble Code (DTC) Type Definitions

Scan Tool Reference

Control Module References 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, and all readings should be within 1.5 Volts 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.
    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.
  2. Remove the drive motor generator battery cover. Refer to 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 V across all 20 battery voltage reference circuits. All voltages should also be within 1.5 V of each other.
    7. ⇒If not within the specified range, replace the drive motor battery assembly.
  7. If all circuits test normal, replace the drive motor battery control module assembly.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the repair.

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