AutoCodes – GMC – P0B40 GMC

P0B40 GMC Code - Hybrid/Electric Vehicle Battery 2 Circuit

Quick Answer

The Hybrid/Electric Vehicle battery pack contains 288 cells. Common causes include Faulty Hybrid/Electric Vehicle Battery Pack, Faulty Hybrid/Electric Vehicle Battery Interface Control Module. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P0B40 GMC indicates Hybrid/Electric Vehicle Battery 2 Circuit.
Common causes: Common causes include Faulty Hybrid/Electric Vehicle Battery Pack, Faulty Hybrid/Electric Vehicle Battery Interface Control Module.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 787

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Mar 07, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P0B40 GMC Description

The Hybrid/Electric Vehicle battery pack contains 288 cells. Groups of three cells are welded together in parallel. There are a total of 96 cell groups in the hybrid/EV battery pack assembly. These cell groups are electrically connected in-series. Each individual cell group is rated at 3.7 V, for a nominal system voltage of 355 V 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 to 96. Battery section two is located behind section one. It is made up of 72 cells/24 cell groups and contains batteries 43 through to 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 to 42. The three battery sections are individually serviceable components.
The battery energy control module monitors the voltage of the 96 battery cell groups through the four hybrid/EV battery interface control modules. Voltage sense circuits are attached to each individual cell group, and these sense circuits terminate at a connector located on the top surface of the battery section. A serviceable auxiliary battery wiring harness joins this connector to a hybrid/EV battery interface control module, also located on the top surface of the battery section. The hybrid/EV battery interface control module encodes the voltage reading and transmits it to the battery energy control module through the battery control harness. There is one hybrid/EV battery interface control module located on battery sections one and two, and two hybrid/EV battery interface control modules associated with battery section three. The hybrid/EV battery interface control module, battery energy control module wiring harness, auxiliary battery wiring 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.

OBDII Code P0B40 GMC - Hybrid/Electric Vehicle Battery 2 Circuit - AutoCodes.com — P0B40 GMC Code - Hybrid/Electric Vehicle Battery 2 Circuit

What does this mean?

What are the Possible Causes of the DTC P0B40 GMC?

Faulty Hybrid/Electric Vehicle Battery Pack
Faulty Hybrid/Electric Vehicle Battery Interface Control Module

How to Fix the DTC P0B40 GMC?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0B40 GMC code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P0B40 GMC Code

1. What does the OBDII code P0B40 mean on a GMC vehicle?

The P0B40 code indicates an issue with the Hybrid/Electric Vehicle Battery 2 Circuit, meaning the powertrain control module (PCM) has detected a fault in the electrical circuit for the second battery module or block.

2. What are the common symptoms of a P0B40 code?

Symptoms may include the hybrid system warning light illuminating, reduced fuel economy, limited power or drivability issues, or failure of the vehicle to switch to electric mode.

3. What causes the P0B40 code to appear?

Common causes include a faulty battery module, damaged or corroded wiring or connectors, a defective battery control module, or software issues in the PCM.

4. Can I drive my GMC vehicle with a P0B40 code?

Driving with this code is not recommended, as it could result in reduced performance, further damage to the hybrid system, or safety risks.

5. How is the P0B40 code diagnosed?

A technician will use a scan tool to read the code, inspect the battery circuit wiring and connectors, and test the battery modules and control module for faults.

6. What repairs are commonly needed for a P0B40 code?

Repairs may include replacing the faulty battery module, repairing or replacing damaged wiring, cleaning corroded connections, or updating the PCM software.

7. How much does it cost to repair a P0B40 code?

Costs vary depending on the specific issue, but replacing a hybrid battery module can range from $1,000 to $6,000, while wiring repairs are typically less expensive.

8. Can a weak 12V battery cause a P0B40 code on a GMC hybrid?

While unlikely, a weak 12V battery could indirectly affect electrical systems, so itâ€™s worth testing and replacing the 12V battery if necessary.

9. Is the P0B40 code specific to GMC vehicles?

No, the P0B40 code is a generic OBDII code that can appear on other hybrid or electric vehicles, but the exact diagnostics and repairs may vary by manufacturer.

10. How can I prevent the P0B40 code from occurring again?

Regular maintenance, inspecting battery connections for corrosion, and keeping the hybrid system software updated can help prevent this code from reoccurring.