AutoCodes – Generic – P1B4F

P1B4F Code - Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage

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: P1B4F indicates Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage.
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 1,191

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 09, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1B4F 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 P1B4F - Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage - AutoCodes.com — P1B4F Code - Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P1B4F?

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

How to Fix the DTC P1B4F?

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 P1B4F 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

P1B4F Buick — Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage
P1B4F Cadillac — Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage
P1B4F Chevrolet — Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage
P1B4F GMC — Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage
P1B4F Saturn — Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage

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 P1B4F Code

1. What are common symptoms of OBDII code P1B4F (Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage)?

- Common symptoms include poor fuel efficiency, loss of power, and difficulty starting the vehicle.

2. What can cause OBDII code P1B4F to trigger?

- This code can be triggered by issues such as a faulty battery, damaged battery cells, or problems within the 36 circuit of the hybrid/electric vehicle battery.

3. How serious is OBDII code P1B4F (Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage)?

- This code is considered serious as it can lead to performance issues and potential damage to the vehicle's battery system if left unresolved.

4. Can I still drive my vehicle with OBDII code P1B4F present?

- It is not recommended to drive the vehicle with this code present, as it can lead to further damage to the battery system and compromise the vehicle's overall performance.

5. How can I diagnose the cause of OBDII code P1B4F (Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage)?

- Diagnosing this code typically involves using a scan tool to check the battery voltage levels, inspecting the battery connections, and testing the 36 circuit for any faults.

6. What are some possible repair tips for fixing OBDII code P1B4F?

- Repair tips may include replacing the battery if it is faulty, repairing any damaged battery cells, checking and repairing wiring connections in the 36 circuit, and resetting the code after repairs are completed.

7. Is it necessary to take the vehicle to a professional mechanic for OBDII code P1B4F repair?

- While some DIY enthusiasts may attempt to troubleshoot and repair this issue, it is recommended to take the vehicle to a professional mechanic with experience in hybrid/electric vehicles for proper diagnosis and repair.

8. Can a low voltage warning for the hybrid/electric vehicle battery be related to OBDII code P1B4F?

- Yes, a low voltage warning can be related to this OBDII code, as low voltage in the battery system can trigger the code and cause performance issues.

9. Are there any preventive measures to avoid OBDII code P1B4F in the future?

- Regular maintenance of the hybrid/electric vehicle battery, monitoring voltage levels, and addressing any issues promptly can help prevent the occurrence of this code in the future.

10. How long does it typically take to repair OBDII code P1B4F (Hybrid/Electric Vehicle Battery 36 Circuit Low Voltage)?

- The repair time for this code can vary depending on the underlying cause and the extent of the repairs needed. It is best to consult with a professional mechanic for a more accurate timeframe.