AutoCodes – Generic – P1B28

P1B28 Code - Hybrid/Electric Vehicle Battery 27 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: P1B28 indicates Hybrid/Electric Vehicle Battery 27 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 2,561

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 08, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1B28 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 P1B28 - Hybrid/Electric Vehicle Battery 27 Circuit - AutoCodes.com — P1B28 Code - Hybrid/Electric Vehicle Battery 27 Circuit

What does this mean?

What are the Possible Causes of the DTC P1B28?

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

How to Fix the DTC P1B28?

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 P1B28 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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Need Help with the Code?

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Information for Specific Makes

P1B28 Buick — Hybrid/Electric Vehicle Battery 27 Circuit
P1B28 Cadillac — Hybrid/Electric Vehicle Battery 27 Circuit
P1B28 Chevrolet — Hybrid/Electric Vehicle Battery 27 Circuit
P1B28 GMC — Hybrid/Electric Vehicle Battery 27 Circuit
P1B28 Saturn — Hybrid/Electric Vehicle Battery 27 Circuit

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 P1B28 Code

1. What are common symptoms of OBDII code P1B28 (Hybrid/Electric Vehicle Battery 27 Circuit)?

- Common symptoms include reduced hybrid/electric vehicle performance, decreased fuel efficiency, and potential issues with the battery system.

2. What are possible causes of OBDII code P1B28?

- Possible causes include a faulty battery 27 circuit, issues with the battery management system, damaged wiring, or a malfunctioning battery temperature sensor.

3. How serious is OBDII code P1B28 (Hybrid/Electric Vehicle Battery 27 Circuit)?

- This code indicates a problem with the hybrid/electric vehicle battery circuit, which can affect vehicle performance and fuel efficiency. It should be addressed promptly to prevent further damage.

4. Can I continue driving with OBDII code P1B28 active?

- It is not recommended to continue driving with this code active, as it can lead to further issues with the hybrid/electric vehicle system. It's best to have the vehicle inspected and repaired as soon as possible.

5. How can I diagnose OBDII code P1B28?

- Diagnosis typically involves using a scan tool to retrieve the code, inspecting the battery 27 circuit, checking for wiring damage, and testing the battery temperature sensor.

6. What are some repair tips for fixing OBDII code P1B28?

- Repair tips may include repairing or replacing damaged wiring, replacing the battery temperature sensor, resetting the battery management system, or seeking assistance from a qualified technician.

7. Can a DIY enthusiast fix OBDII code P1B28 at home?

- While some basic troubleshooting can be done at home, diagnosing and repairing issues related to the hybrid/electric vehicle battery system may require specialized knowledge and equipment. It's recommended to seek professional help for proper diagnosis and repair.

8. How much does it cost to repair OBDII code P1B28?

- Repair costs can vary depending on the underlying cause of the code, the extent of the damage, and labor rates in your area. It's advisable to obtain multiple quotes from reputable repair shops for an accurate estimate.

9. Will OBDII code P1B28 reset on its own?

- In some cases, the code may reset on its own if the underlying issue is temporary. However, it's best to have the vehicle inspected to determine the root cause of the problem and prevent potential reoccurrence.

10. How can I prevent OBDII code P1B28 from appearing again in the future?

- Regular maintenance of the hybrid/electric vehicle system, including checking the battery connections, monitoring battery performance, and addressing any warning lights promptly, can help prevent OBDII code P1B28 from reappearing.