AutoCodes – Generic – P1A29

P1A29 Code - Hybrid Battery 2 Circuit Low Voltage

Quick Answer

Battery voltage sensors allow the Energy Storage Control Module (ESCM) to monitor the voltage of the batteries in the Energy Storage Box (ESB). Common causes include Faulty Energy Storage Box (ESB) Battery, Faulty Battery Energy Control Module (BECM), Battery Energy Control Module (BECM) harness is open or shorted. 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: P1A29 indicates Hybrid Battery 2 Circuit Low Voltage.
Common causes: Common causes include Faulty Energy Storage Box (ESB) Battery, Faulty Battery Energy Control Module (BECM), Battery Energy Control Module (BECM) harness is open or shorted.
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 2,603

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 Feb 15, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1A29 Description

Battery voltage sensors allow the Energy Storage Control Module (ESCM) to monitor the voltage of the batteries in the Energy Storage Box (ESB). The batteries apply voltage to internal input resistors that are connected to the signal circuits of the battery voltage sensors. The module provides ground to the battery voltage sensors through the reference circuit. The ESCM monitors the voltage drop across the battery voltage sensors and uses the inputs for hybrid calculations. When the battery voltage is high, the resistances of the sensors are high and the voltage signals are high. When the battery voltage is low, the resistances of the sensors are low and the voltage signals are low.

OBDII Code P1A29 - Hybrid Battery 2 Circuit Low Voltage - AutoCodes.com — P1A29 Code - Hybrid Battery 2 Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P1A29?

Faulty Energy Storage Box (ESB) Battery
Faulty Battery Energy Control Module (BECM)
Battery Energy Control Module (BECM) harness is open or shorted
Battery Energy Control Module (BECM) circuit poor electrical connection

How to Fix the DTC P1A29?

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 P1A29 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

P1A29 Buick — Hybrid Battery 2 Circuit Low Voltage
P1A29 Cadillac — Hybrid Battery 2 Circuit Low Voltage
P1A29 Chevrolet — Hybrid Battery 2 Circuit Low Voltage
P1A29 GMC — Hybrid Battery 2 Circuit Low Voltage
P1A29 Saturn — Hybrid Battery 2 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 P1A29 Code

1. What are common symptoms of OBDII code P1A29 (Hybrid Battery 2 Circuit Low Voltage)?

- Common symptoms include a decrease in fuel efficiency, difficulty starting the vehicle, and the illumination of the check engine light.

2. What can cause the OBDII code P1A29 (Hybrid Battery 2 Circuit Low Voltage) to trigger?

- This code can be triggered by issues such as a faulty hybrid battery cell, poor battery connections, or problems with the battery management system.

3. How serious is the OBDII code P1A29 (Hybrid Battery 2 Circuit Low Voltage)?

- This code should be addressed promptly as it can affect the performance and efficiency of the hybrid vehicle.

4. Can I continue driving my vehicle with the OBDII code P1A29 (Hybrid Battery 2 Circuit Low Voltage)?

- It is not recommended to drive the vehicle for an extended period with this code present, as it can lead to further damage to the hybrid system.

5. How can I diagnose the cause of OBDII code P1A29 (Hybrid Battery 2 Circuit Low Voltage)?

- A professional diagnostic scan tool can be used to retrieve specific data related to the hybrid battery voltage and system components.

6. What are some repair tips for addressing OBDII code P1A29 (Hybrid Battery 2 Circuit Low Voltage)?

- Repair tips may include checking and cleaning battery connections, testing the individual battery cells, and ensuring proper functioning of the battery management system.

7. Is it possible to reset the OBDII code P1A29 (Hybrid Battery 2 Circuit Low Voltage) without fixing the underlying issue?

- While clearing the code may temporarily turn off the check engine light, it is important to address the root cause to prevent further problems.

8. Can a DIY enthusiast fix OBDII code P1A29 (Hybrid Battery 2 Circuit Low Voltage) at home?

- Depending on the level of expertise and access to tools, some simple troubleshooting steps like checking connections can be done at home, but more complex issues may require professional help.

9. How much does it typically cost to repair OBDII code P1A29 (Hybrid Battery 2 Circuit Low Voltage)?

- Costs can vary based on the specific cause of the code, but repairs related to the hybrid battery system can range from a few hundred to several thousand dollars.

10. Are there any preventive maintenance measures to avoid OBDII code P1A29 (Hybrid Battery 2 Circuit Low Voltage)?

- Regularly servicing the hybrid system, monitoring battery health, and addressing any warning signs promptly can help prevent issues leading to this code.