AutoCodes – Buick – P1B5A Buick

P1B5A Buick Code - Hybrid/Electric Vehicle Battery 40 Circuit Performance

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: P1B5A Buick indicates Hybrid/Electric Vehicle Battery 40 Circuit Performance.
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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 850

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 12, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P1B5A Buick 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 P1B5A Buick - Hybrid/Electric Vehicle Battery 40 Circuit Performance - AutoCodes.com — P1B5A Buick Code - Hybrid/Electric Vehicle Battery 40 Circuit Performance

What does this mean?

What are the Possible Causes of the DTC P1B5A Buick?

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

How to Fix the DTC P1B5A Buick?

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 P1B5A Buick 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.

Need more information about the P1B5A Buick code?

Need more information on how to fix the P1B5A Buick code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1B5A Buick code diagnosed by a professional: Find a repair shop in your area

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 P1B5A Buick Code

1. What does the OBDII code P1B5A mean on a Buick?

P1B5A indicates a performance issue in the Hybrid/Electric Vehicle Battery 40 Circuit, suggesting a possible problem with the high-voltage battery or related components.

2. What are the common symptoms of code P1B5A in a Buick?

Symptoms may include the hybrid system warning light, reduced fuel efficiency, diminished electric range, or the vehicle entering limp mode.

3. What causes the P1B5A code in a Buick?

Common causes include faulty battery sensors, damaged wiring or connectors in the battery circuit, or an issue with the battery control module.

4. Can I still drive my Buick with the P1B5A code?

Itâ€™s not recommended to drive with this code, as it may lead to further damage to the hybrid system or cause the vehicle to lose power unexpectedly.

5. How do technicians diagnose the P1B5A code?

Technicians use a scan tool to check the code, inspect the battery circuit for damage, test the battery control module, and monitor voltage and resistance readings.

6. How do I fix the P1B5A code on a Buick?

Repairs may involve replacing damaged wiring, repairing battery circuit connections, or replacing a faulty battery sensor or control module.

7. Is the P1B5A code covered under warranty for my Buick?

If your vehicle is still under the hybrid or electric powertrain warranty, repairs related to the battery circuit may be covered. Check your warranty terms for confirmation.

8. How much does it cost to repair the P1B5A code on a Buick?

Repair costs vary depending on the issue but can range from $200 for minor wiring repairs to over $1,000 for battery module or sensor replacements.

9. Can a weak 12V battery trigger the P1B5A code in a Buick?

A weak 12V battery is unlikely to cause this specific code, as it relates to the high-voltage battery circuit, not the 12V electrical system.

10. How can I prevent the P1B5A code from occurring in my Buick?

Regular maintenance, including checking battery connections and inspecting the hybrid system for wear or damage, can help prevent this code from appearing.