FREE REPAIR MANUALS & LABOR GUIDES 1982-2013 Vehicles
Courtesy of Operation CHARM: Car repair manuals for everyone.
Home >> Chevrolet >> 2012 >> Volt L4-1.4L Elect >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> P Code Charts >> P1A07

P1A07




DTC P1A07, P1E93, P1E99, P1E9F, or P1EA5

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 P1A07
- Battery Energy Control Module 5 V Reference Circuit

DTC P1E93
- Hybrid/EV Battery Interface Control Module 1 5 V Reference Circuit

DTC P1E99
- Hybrid/EV Battery Interface Control Module 2 5 V Reference Circuit

DTC P1E9F
- Hybrid/EV Battery Interface Control Module 3 5 V Reference Circuit

DTC P1EA5
- Hybrid/EV Battery Interface Control Module 4 5 V Reference Circuit

Circuit/System Description

The drive motor battery contains 288 cells. Groups of three cells are welded together in parallel. There are a total of 96 cell groups in the drive motor battery assembly. These cell groups are electrically connected in series. Each individual cell group is rated at 3.7 volts, for a nominal system voltage of 355 volts direct current. The battery cells are also grouped together into three sections. The first 90 cells / 30 cell groups make up battery section one. This section is adjacent to the cowl and contains batteries 67 through 96. Battery section two is located behind section one. It is made up of 72 cells / 24 cell groups and contains batteries 43 through 66. The transverse battery section is section number three, it is made up of the remaining 126 cells / 42 cell groups and contains batteries 1 through 42. The three battery sections are individually serviceable components.

The battery energy control module monitors the voltage of the 96 cell groups. Voltage sense lines are attached to each individual cell groups, and these sense lines terminate at a connector located on the top surface of the battery section. A serviceable voltage sense harness joins this connector to a drive motor battery high voltage interface control module, also located on the top surface of the battery section. The drive motor battery high voltage interface control module encodes the voltage reading and transmits it to the battery energy control module through the battery control harness. There is one drive motor battery high voltage interface control module located on battery sections one and two, and two drive motor battery high voltage interface control modules associated with battery section three. The drive motor battery high voltage interface control module, voltage sense harnesses, battery control harness and battery energy control module are all considered serviceable components.

The battery energy control module will determine when a fault condition is present. Diagnostics and system status are communicated from the battery energy control module to hybrid/EV powertrain control module 2 through serial data. The hybrid/EV powertrain control module 2 is the host controller for diagnostic trouble code information.

Conditions for Running the DTC

P1A07
* The battery energy control module is awake and communicating.
* The 12 V battery voltage greater than or equal to 9 V.

P1E93, P1E99, P1E9F, P1EA5
* Ignition cycles from ON to OFF.
* The battery energy control module is awake and communicating.
* No loss of communications between the battery energy control module and any of the hybrid/EV battery interface control modules.
* The 2nd protection circuit diagnostic is not running.

Conditions for Setting the DTC

P1A07

The battery energy control module has detected a fault on the internal 5 V reference circuit.

P1E93, P1E99, P1E9F, P1EA5
* The 2nd protection circuit diagnostic is not running.
* A hybrid/EV battery interface control module has detected a fault on the internal 5 V reference circuit.

Action Taken When the DTC Sets

* DTCs P1A07 P1E93, P1E99, P1E9F, or P1EA5 are type B DTCs.
* If any of these DTCs are set, the vehicle will operate in a reduced power mode and electric only engine ON.

Conditions for Clearing the DTC

DTCs P1A07 P1E93, P1E99, P1E9F, or P1EA5 are type B DTCs.

Reference Information
Schematic Reference

Hybrid Energy Storage Schematics Hybrid Energy Storage Schematics
Connector End View Reference

Component Connector End Views Hybrid/EV Battery Pack X1
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-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 Volt Battery Pack will utilize an exchange program. Please consult the most recent revision of bulletin/PI #PIP4841, available in Service Information (SI), for a list of approved Volt Battery Pack service procedures. Components that may be removed and serviced without exchanging the complete battery pack are identified in the bulletin/PI. Please contact the GM Technical Assistance Center (1-877-446-8227) if you have any questions.


1. If DTC P1A07 is set, replace the K16 battery energy control module.
2. If DTC P1E93, P1E99, P1E9F, or P1EA5 are set, replace the appropriate hybrid/EV battery interface control module.

Repair Instructions

Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.

Control Module References Programming and Relearning for battery energy control module or hybrid/EV interface control modules 1-4 replacement, programming and setup

pro multis Credits:Operation CHARM About Operation CHARM