B1671 – OBD-II DTC

OBD-II DTC B1671 – Battery Module Voltage Out Of Range

DTC B1671 meaning

DTC B1671 refers to a diagnostic trouble code indicating that the battery module voltage is out of range. This code is typically associated with hybrid or electric vehicles that utilize a battery management system to monitor the voltage levels of the battery modules. When the voltage detected by the system falls outside the expected range, it triggers this code, signaling a potential issue with the battery or its connections.

DTC B1671 symptoms

Common symptoms associated with DTC B1671 may include:

  • Warning lights on the dashboard, such as the check engine light or battery warning light.
  • Reduced performance of the vehicle, particularly in hybrid or electric modes.
  • Increased fuel consumption in hybrid vehicles.
  • Possible inability to start the vehicle or intermittent starting issues.
  • Battery management system alerts or notifications.

DTC B1671 causes

Several factors can lead to the triggering of DTC B1671, including:

  • Faulty battery modules or cells that are not holding the correct voltage.
  • Loose or corroded connections within the battery management system.
  • Defective battery management system (BMS) components.
  • Issues with the vehicle’s charging system, such as a failing alternator.
  • Software glitches or calibration issues within the vehicle’s control modules.

DTC B1671 seriousness

DTC B1671 can be considered a serious issue, especially in hybrid and electric vehicles. If left unaddressed, it may lead to:

  • Decreased vehicle performance and efficiency.
  • Potential damage to the battery system, leading to costly repairs.
  • Increased risk of battery failure or safety hazards.
  • Inability to operate the vehicle in hybrid or electric mode.

How to diagnose DTC B1671

To diagnose DTC B1671, follow these steps:

  1. Use an OBD-II scanner to confirm the presence of DTC B1671.
  2. Check for any additional trouble codes that may provide more context.
  3. Inspect the battery modules and connections for any visible damage or corrosion.
  4. Measure the voltage of each battery module to ensure they are within the specified range.
  5. Test the battery management system for proper operation and calibration.
  6. Review the vehicle’s service history for any previous issues related to the battery or charging system.

How to fix DTC B1671 step-by-step instructions

To fix DTC B1671, follow these steps:

  1. Address any loose or corroded connections by cleaning and tightening them.
  2. Replace any faulty battery modules or cells that are not holding the correct voltage.
  3. If the battery management system is defective, consider replacing or reprogramming it.
  4. Inspect and repair the vehicle’s charging system, including the alternator and related components.
  5. Clear the DTC using an OBD-II scanner and perform a test drive to ensure the issue is resolved.
  6. Monitor the vehicle for any reoccurrence of the code or related symptoms.

How to erase DTC B1671

To erase DTC B1671, follow these steps:

  1. Connect an OBD-II scanner to the vehicle’s diagnostic port.
  2. Turn on the vehicle’s ignition without starting the engine.
  3. Navigate to the trouble codes section of the scanner.
  4. Select the option to clear or erase the codes.
  5. Confirm the action and wait for the scanner to complete the process.
  6. Disconnect the scanner and start the vehicle to ensure the code does not reappear.

Recommended tools for OBD-II diagnostics

Explore our expert picks: The Best OBD2 Scanners for 2025

Easy-to-use Multimeter for reliable diagnostics: AstroAI Auto-ranging Multimeter

Some of the links on this page may be affiliate links, which means we may earn a small commission if you make a purchase. This helps us keep our DTC database up to date and provide valuable content for free. We only recommend products that we have tested and believe to be the best in their class.