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Home >> Chevrolet >> 2012 >> Volt L4-1.4L Elect >> Repair and Diagnosis >> A L L Diagnostic Trouble Codes ( DTC ) >> Testing and Inspection >> P Code Charts >> P1EAB

P1EAB




DTC P1EAB or P1EAC

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 P1EAB
- Battery Energy Control Module Hybrid/EV Battery Cell High Voltage

DTC P1EAC
- Hybrid/EV Battery Cell Overvoltage Signal Circuit Performance

Circuit/System Description

The 2nd protection is a redundant method to monitor cell group overvoltage. The four hybrid/EV battery interface control modules independently read and test each cell group. The 2nd protection circuit fault is the actual hardwire signal from the four hybrid/EV battery interface control modules to the battery energy control module and terminating in the hybrid/EV powertrain control module 2. The hybrid/EV powertrain control module 2 diagnoses this line to determine when a cell group overvoltage condition exists.

The 2nd protection self test diagnostic is used to check the signal circuit. The battery energy control module performs this test, once, every power down cycle. When run/crank input signal transitions low and after a calibrated delay, the battery energy control module informs the hybrid/EV powertrain control module 2, via serial data communication bus that it is about to run the diagnostics on the 2nd protection circuit. The battery energy control module then proceeds to command, via internal serial data, each hybrid/EV battery interface control module to run the check on its hardwire output. Each of the four hybrid/EV battery interface control modules pulls the signal circuit low and releases it, in sequence. If any pulses are missing, the battery energy control module is able to diagnose which hybrid/EV battery interface control module(s) has a fault, and sets a related fault, and sends this information to the hybrid/EV powertrain control module 2 on the serial data

Conditions for Running the DTC

P1EAB
* The battery energy control module and hybrid/EV powertrain control module 2 are awake and communicating.
* DTC P1EAC or U185A is not set

P1EAC
* The battery energy control module and hybrid/EV powertrain control module 2 are awake and communicating.
* Ignition cycles from ON to OFF.
* Ignition is OFF for 500 ms.
* The 12 V battery voltage greater than or equal to 9 V.
* None of the following DTCs are set; P1E8E, P1E94, P1E9A, or P1EA0.
* No loss of communications between the battery energy control module and any of the hybrid/EV battery interface control modules.

Conditions for Setting the DTC

P1EAB

A cell overvoltage is detected.

P1EAC

The hybrid/EV powertrain control module 2 has detected a fault with the 2nd protection fault flag.

Action Taken When the DTC Sets

* DTCs P1EAB and P1EAC are type A DTCs.
* If any of these DTCs are set, the vehicle will operate in a reduced power mode and electric only engine ON.
* Once Vehicle Power has been turned OFF all of the contactors will be prevented from closing.

Conditions for Clearing the DTC

* DTCs P1EAB and P1EAC are type A DTCs.
* After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes to prevent DTCs from resetting.
* Vehicle Power cycled from ON to OFF after code clear

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
* EL-50211 - Low Voltage Jumper Harness Extension

For equivalent regional tools, refer to Special Tools Tools and Equipment.

Circuit/System Verification

Verify that DTC P0B3B, P0B3D, P0B3E, P0B40, P0B42, P0B43, P0B45, P0B47, P0B48, P0B4A, P0B4C, P0B4D, P0B4F, P0B51, P0B54, P0B52, P0B56, P0B57, P0B59, P0B5B, P0B5C, P0B5E, P0B60, P0B61, P0B63, P0B65, P0B66, P0B68, P0B6A, P0B6B, P0B6D, P0B6F, P0B70, P0B72, P0B74, P0B75, P0B77, P0B79, P0B7A, P0B7C, P0B7E, P0B7F, P0B81, P0B83, P0B84, P0B86, P0B88, P0B89, P0B8B, P0B8D, P0B8E, P0B90, P0B92, P0B93, P0B95, P0B97, P0B98, P0B9A, P0B9C, P0B9D, P0B9F, P0BA1, P0BA2, P0BA4, P0BA6, P0BA7, P0BA9, P0BAB, P0BAC, P0BAE, P0BB0, P0BB1, P0BB3, P0BB5, P0BB6, P0BB8, P0BBA, P0BBB, P1B17, P1B18, P1B1A, P1B1B, P1B1D, P1B1E, P1B20, P1B21, P1B23, P1B24, P1B26, P1B27, P1B28, P1B29, P1B2A, P1B2B, P1B2C, P1B2D, P1B46, P1B47, P1B4A, P1B4C, P1B4D, P1B4F, P1B50, P1B52, P1B53, P1B55, P1B56, P1B58, P1B59, P1B5B, P1B5C, P1B5E, P1B5F, P1B61, P1B64, P1B62, P1B65, P1B67, P1B68, P1B6A, P1B6B, P1B6D, P1B6E, P1B70, P1B71, P1B73, P1B74, P1B76, P1B77, P1B79, P1B7A, P1B7C, P1B7D, P1B7F, P1B80, P1B82, P1B83, P1B85, P1B86, P1B88, P1B89, P1B8B, P1B8C, P1B8E, P1B8F, P1B91, P1B92, P1B94, P1B95, P1B97, P1B98, P1B9A, P1B9B, P1B9D, P1B9E, P1BA0, P1BA1, P1BA3, P1BA4, P1BA6, P1BA7, P1BA9, P1BAA, P1BAC, P1BAD, P1BAF, P1BB0, P1BB2, P1BB3, P1BB5, P1BB6, P1BB8, P1BB9, P1BBB, P1BBC, P1BBE, P1BBF, P1BC1, P1BC2, P1BC4, P1BC5, P1BC7, P1BC8, P1BCA, P1BCB, P1BCD, P1BCE, P1BD0, P1BD1, P1BD3, P1BD4, P1BD6, P1BD7, P1BD9, P1BDA, P1BDC, P1BDD, P1BDF, P1BE0, P1BE2, P1BE3, P1BE5, P1BE6, P1BE8, P1BE9, P1BEB, P1BEC, P1BEE, P1BEF, P1BF1, P1BF2, P1BF4, P1BF5, P1BF7, P1BF8, P1BFA, P1BFB, P1BFD, P1BFE, P1E02, P1E03, P1E05, P1E06, P1E4C, P1E4D, P1E4E, P1E4F, P1E50, P1E51, P1E52, P1E53, P1E54, P1E55, P1E56, P1E57, P1E58, P1E59, P1E5A, P1E5B, P1E5C, P1E5D, P1E5E, P1E5F, P1E60, P1E61, P1E62, P1E63, P1E64, P1E65, P1E66, P1E67, P1E68, P1E69, P1E6A, P1E6B, P1E6C, P1E6D, P1E6E, P1E6F, P1E70, P1E71, P1E72, P1E73, P1E74, P1E75, P1E76, P1E77, P1E78, P1E79, P1E7A, P1E7B, P1E7C, P1E7D, P1E7E, P1E7F, P1E80, P1E81, P1E82, P1E83, P1E84, P1E85, P1E86, P1E87, P1E88, P1E89, P1E8A, U2603, U2604, U2605, or U2606 is not set.

If DTC is set, refer to Diagnostic Trouble Code (DTC) List - Vehicle Diagnostic Trouble Code (DTC) List - Vehicle.

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 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. Vehicle OFF, disable the high voltage at the A4 hybrid/EV battery pack. Refer to High Voltage Disabling High Voltage Disabling
2. Connect the 12 V battery.
3. Disconnect the X2 harness connector at the A28 hybrid/EV battery contactor assembly.
4. Vehicle in Service Mode, test for 4.8-5.2 V between the overvoltage signal circuit terminal 6 and ground.

• If less than the specified range, test the overvoltage signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.
• If greater than the specified range, test the overvoltage signal circuit for a short to voltage. If the circuit tests normal, replace the K114B hybrid/EV powertrain control module 2. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.

5. Vehicle OFF, connect EL-50211 - low voltage jumper harness extension.
6. Disconnect the X1 harness connector at the K16 battery energy control module.
7. Vehicle in Service Mode, test for 4.8-5.2 V between the overvoltage signal circuit terminal 21 and ground.

• If less than the specified range, replace the A28 hybrid/EV battery contactor assembly. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.
• If greater than the specified range, replace the A28 hybrid/EV battery contactor assembly. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.

8. Vehicle OFF, reconnect X1.
9. Disconnect the X1 harness connector at the K112A hybrid/EV battery interface control module 1.
10. Vehicle in Service Mode, test for 4.8-5.2 V between the overvoltage signal circuit terminal 13 and ground.

• If less than the specified range, test the overvoltage signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K16 battery energy control module. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.
• If greater than the specified range, test the overvoltage signal circuit for a short to voltage. If the circuit tests normal, replace the K16 battery energy control module. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.

11. Vehicle OFF, connect the X1 harness connector at the K112A hybrid/EV battery interface control module 1.
12. Disconnect the X1 harness connector at the K112B hybrid/EV battery interface control module 2.
13. Vehicle in Service Mode, test for 4.8-5.2 V between the overvoltage signal circuit terminal 13 and ground.

• If less than the specified range, test the overvoltage signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K112A hybrid/EV battery interface control module 1. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.
• If greater than the specified range, test the overvoltage signal circuit for a short to voltage. If the circuit tests normal, replace the K112A hybrid/EV battery interface control module 1. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.

14. Vehicle OFF, connect the X1 harness connector at the K112B hybrid/EV battery interface control module 2.
15. Disconnect the X1 harness connector at the K112C hybrid/EV battery interface control module 3.
16. Vehicle in Service Mode, test for 4.8-5.2 V between the overvoltage signal circuit terminal 13 and ground.

• If less than the specified range, test the overvoltage signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K112B hybrid/EV battery interface control module 2. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.
• If greater than the specified range, test the overvoltage signal circuit for a short to voltage. If the circuit tests normal, replace the K112B hybrid/EV battery interface control module 2. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.

17. Vehicle OFF, connect the X1 harness connector at the K112C hybrid/EV battery interface control module 3.
18. Disconnect the X1 harness connector at the K112D hybrid/EV battery interface control module 4.
19. Vehicle in Service Mode, test for 4.8-5.2 V between the overvoltage signal circuit terminal 13 and ground.

• If less than the specified range, test the overvoltage signal circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the K112C hybrid/EV battery interface control module 3. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.
• If greater than the specified range, test the overvoltage signal circuit for a short to voltage. If the circuit tests normal, replace the K112C hybrid/EV battery interface control module 3. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.

20. If all circuits test normal, replace the K112D hybrid/EV battery interface control module 4. After the repair, with a scan tool, perform the Clear Secured High Voltage DTCs Reading and Clearing Diagnostic Trouble Codes.

Repair Instructions

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

* Drive Motor Battery Wire Junction Block Relay Replacement Drive Motor Battery Wire Junction Block Relay Replacement
* Control Module References Programming and Relearning for battery energy control module, hybrid/EV interface control modules 1-4, or hybrid/EV powertrain control module 2 replacement, programming and setup

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