Engine-CodesBuick – P1E91 Buick

P1E91 Buick Code - Hybrid/EV Battery Interface Control Module 1 Long Term Memory Performance

Quick Answer

The P1E91 diagnostic trouble code for Buick vehicles indicates an issue with the Hybrid/EV Battery Interface Control Module 1 Long Term Memory Performance. Common causes include Faulty Wiring Connections: Corrosion, damage, or loose connections in the wiring harness can disrupt communication between the control module and the battery system, Malfunctioning Control Module: The Hybrid/EV Battery Interface Control Module itself may be faulty, causing issues with data storage and retrieval, Software Glitches: Software errors or bugs in the control module's programming can cause performance issues. 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
P1E91 Buick indicates Hybrid/EV Battery Interface Control Module 1 Long Term Memory Performance.
Common causes
Common causes include Faulty Wiring Connections: Corrosion, damage, or loose connections in the wiring harness can disrupt communication between the control module and the battery system, Malfunctioning Control Module: The Hybrid/EV Battery Interface Control Module itself may be faulty, causing issues with data storage and retrieval, Software Glitches: Software errors or bugs in the control module's programming can cause performance issues.
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.
Table of contents Created and updated by William Orellana on Sep 10, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P1E91 Buick Description

The P1E91 diagnostic trouble code for Buick vehicles indicates an issue with the Hybrid/EV Battery Interface Control Module 1 Long Term Memory Performance. This specific module is responsible for managing the interaction between the vehicle's hybrid or electric battery system and the rest of the vehicle's electronics. The Long Term Memory Performance aspect of the code suggests that there is a problem with how the module is storing or retrieving data over an extended period.

OBDII Code P1E91 Buick - Hybrid/EV Battery Interface Control Module 1 Long Term Memory Performance
P1E91 Buick Code - Hybrid/EV Battery Interface Control Module 1 Long Term Memory Performance

Common Causes of P1E91 Buick

  1. Faulty Wiring Connections: Corrosion, damage, or loose connections in the wiring harness can disrupt communication between the control module and the battery system.
  2. Malfunctioning Control Module: The Hybrid/EV Battery Interface Control Module itself may be faulty, causing issues with data storage and retrieval.
  3. Software Glitches: Software errors or bugs in the control module's programming can cause performance issues.
  4. Battery System Problems: Issues with the hybrid or electric battery, such as low voltage or a failing cell, can trigger this code.
  5. Environmental Factors: Extreme temperatures or moisture exposure can also impact the performance of the battery interface control module.

Symptoms of P1E91 Buick

  1. Check Engine Light: The most common symptom associated with this code is the illumination of the check engine light on the vehicle's dashboard.
  2. Reduced Fuel Efficiency: Drivers may notice a decrease in fuel efficiency as the hybrid or electric system struggles to operate efficiently.
  3. Loss of Electric Drive: In some cases, the vehicle may lose its electric drive capability, relying solely on the internal combustion engine.
  4. Power Delivery Issues: Acceleration may feel sluggish or uneven due to problems with the hybrid system.
  5. Limp Mode: The vehicle may enter a "limp mode" to protect itself from further damage, severely limiting performance.

How to Fix P1E91 Buick

  1. Diagnostics: Begin by using a scan tool to retrieve the fault codes and perform a comprehensive diagnosis of the Hybrid/EV system.
  2. Inspect Wiring: Check the wiring connections for any signs of damage, corrosion, or loose connections. Repair or replace as needed.
  3. Test Control Module: Test the Hybrid/EV Battery Interface Control Module for proper functionality. Replace if necessary.
  4. Software Update: Update the control module's software to the latest version to address any known bugs or glitches.
  5. Battery System Evaluation: Evaluate the hybrid or electric battery system for any potential issues that may be affecting the control module's performance.

Cost to Fix P1E91 Buick

The typical repair costs for addressing a P1E91 code on a Buick vehicle can vary depending on the specific cause of the issue. On average, you can expect to pay between $200 and $800 for parts and labor. Keep in mind that diagnosis time and labor rates at auto repair shops can vary based on factors such as location, vehicle make and model, and engine type. It's advisable to check local rates for a more precise estimate. Remember that neglecting this issue can lead to more expensive repairs down the line, so it's best to address it promptly.

Need more information about the P1E91 Buick code?

Need more information on how to fix the P1E91 Buick code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1E91 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 P1E91 Buick Code

1. What does the OBDII code P1E91 mean on a Buick?

P1E91 indicates an issue with the Hybrid/EV Battery Interface Control Module 1, specifically related to its long-term memory performance.

2. What are the common symptoms of code P1E91 in a Buick?

Symptoms may include a check engine light, reduced hybrid/EV performance, limited vehicle power, or failure to switch between power modes.

3. What causes the P1E91 code to appear on a Buick?

The code can be triggered by corrupted memory in the control module, software glitches, low or unstable battery voltage, or a faulty control module.

4. Can I drive my Buick with the P1E91 code active?

Driving with this code is not recommended, as it may lead to reduced performance or potential damage to the hybrid/EV battery system.

5. How is the P1E91 code diagnosed?

A technician will use a scan tool to retrieve the code, check for related codes, inspect the control module connections, and test the system's voltage and software.

6. How do you fix the P1E91 code on a Buick?

Repairs may involve reprogramming or updating the control module software, repairing wiring issues, or replacing the Hybrid/EV Battery Interface Control Module 1 if faulty.

7. Can a dead 12V auxiliary battery cause the P1E91 code?

Yes, a weak or dead 12V battery can cause voltage inconsistencies that may trigger this code.

8. Does the P1E91 code require a software update?

In some cases, a software update for the Hybrid/EV Battery Interface Control Module may resolve the issue if it’s caused by a memory or programming error.

9. How much does it cost to repair the P1E91 code on a Buick?

Repair costs can vary but typically range from $150 to $800, depending on whether the issue involves software reprogramming or module replacement.

10. Can I clear the P1E91 code without fixing the issue?

Clearing the code without addressing the root cause will not resolve the problem, and the code is likely to return.

Discuss the causes and fixes for P1E91 Buick OBDII Code

Code P1E91 Buick comments

No comments found for this page.