AutoCodes – Generic – P1B29

P1B29 Code - Hybrid/Electric Vehicle Battery 28 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: P1B29 indicates Hybrid/Electric Vehicle Battery 28 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 1,045

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
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Code P1B29 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 P1B29 - Hybrid/Electric Vehicle Battery 28 Circuit - AutoCodes.com — P1B29 Code - Hybrid/Electric Vehicle Battery 28 Circuit

What does this mean?

What are the Possible Causes of the DTC P1B29?

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

How to Fix the DTC P1B29?

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 P1B29 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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Information for Specific Makes

P1B29 Buick — Hybrid/Electric Vehicle Battery 28 Circuit
P1B29 Cadillac — Hybrid/Electric Vehicle Battery 28 Circuit
P1B29 Chevrolet — Hybrid/Electric Vehicle Battery 28 Circuit
P1B29 GMC — Hybrid/Electric Vehicle Battery 28 Circuit
P1B29 Saturn — Hybrid/Electric Vehicle Battery 28 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 P1B29 Code

1. What are the common symptoms of OBDII code P1B29 (Hybrid/Electric Vehicle Battery 28 Circuit)?

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

2. What typically causes the OBDII code P1B29 to trigger?

- This code is usually triggered by a fault in the circuit related to the 28th battery module in a hybrid or electric vehicle's battery pack.

3. How can I diagnose the issue related to the Hybrid/Electric Vehicle Battery 28 Circuit?

- Diagnosis involves using a scan tool to retrieve the specific code, checking the wiring and connections related to the 28th battery module, and testing the battery module itself for faults.

4. Is it safe to continue driving with the P1B29 code present?

- It is not recommended to drive with the P1B29 code, as it can lead to further damage to the hybrid/electric vehicle battery system and may result in decreased performance.

5. What are some potential repair tips for addressing the Hybrid/Electric Vehicle Battery 28 Circuit issue?

- Repair tips include checking and repairing any damaged wiring or connections, replacing the faulty battery module if necessary, and resetting the fault code with a scan tool.

6. Can a DIY enthusiast fix the P1B29 code issue, or is professional assistance required?

- While some basic checks and repairs can be done by a DIY enthusiast, diagnosing and repairing complex issues related to the hybrid/electric vehicle battery system may require professional assistance.

7. How much does it typically cost to repair the Hybrid/Electric Vehicle Battery 28 Circuit problem?

- The cost of repair can vary depending on the extent of the issue, the need for replacement parts, and whether professional labor is required. It is advisable to get a repair estimate from a qualified technician.

8. Are there any preventive maintenance measures to avoid the OBDII code P1B29 from recurring?

- Regularly inspecting and maintaining the hybrid/electric vehicle battery system, ensuring proper charging practices, and addressing any warning signs promptly can help prevent the recurrence of the P1B29 code.

9. Can the P1B29 code be related to other underlying issues in a hybrid/electric vehicle?

- While the P1B29 code specifically relates to the Hybrid/Electric Vehicle Battery 28 Circuit, it is possible for underlying issues in the battery system to trigger related codes. Comprehensive diagnosis is recommended.

10. Is it necessary to reset the OBDII code P1B29 after repairing the Hybrid/Electric Vehicle Battery 28 Circuit issue?

- Yes, it is important to reset the fault code using a scan tool after repairing the Hybrid/Electric Vehicle Battery 28 Circuit issue to clear the warning light and ensure proper functioning of the vehicle.