01 All-New Lexus GX Overtrail (2024) - The Rugged Luxury SUV • 02 Understanding Engine Control Modules (ECMs) and Their Funct… • 03 At What Mileage Do Most Cars Start Having Issues? • 04 The Sneaky Mechanical Piece That Increases Fuel Consumption… • 05 Navigating Truck Accidents: How an 18 Wheeler Truck Lawyer … • 06 Unveiling the Wonders of Auto Pilot in Cars: A Technologica… • 07 Should You Admit Fault in a Car Accident if It's Your Fault? • 08 People Left Concerned After Learning Why Some Hybrids Rando… • 09 B0045: Left Front Side Deploy Loop Short to Ground or Volta… • 10 Mastering Overdrive: A Guide to Efficiency in Automatic Tra… •

DTC codes / P0Bxx · Hybrid propulsion / P0B14

P0B14Hybrid/EV Battery Pack Voltage Sense B Circuit

P0B14 indicates that the hybrid or electric vehicle battery pack voltage sensing circuit B is reporting a voltage outside the expected range or is otherwise implausible to the battery energy control module. The computer has detected a fault in the dedicated wiring, connector, or sensing hardware that monitors a specific section of the high-voltage battery, which prevents accurate state-of-charge and cell balancing calculations.

SystemPowertrain
Code typeGeneric (all makes)
SeverityMedium
Fix difficultyProfessional
AreaHybrid propulsion

Symptoms you may notice

  • Illumination of the hybrid system warning light or service vehicle soon message
  • Often no symptoms besides the warning light, especially if the fault is intermittent
  • Reduced electric-only range or the engine running more frequently than normal
  • The vehicle may enter a fail-safe mode with limited power or disabled hybrid functions
  • Inconsistent state-of-charge readings on the dashboard gauge
  • Possible refusal to start or engage the high-voltage system after the fault sets

Common causes, most likely first

  1. Corroded, loose, or damaged electrical connector at the voltage sense harness or battery pack interface
  2. Open or shorted voltage sense wire between the battery pack and the control module
  3. Faulty voltage sense circuit board or sensing harness internal to the battery pack
  4. Failed battery energy control module or hybrid control module
  5. Internal battery pack fault such as a weak module or cell affecting the sensed voltage
  6. Water intrusion or contamination in the battery pack connector area
  7. Aftermarket accessories or improper previous repairs disturbing the sense wiring

How to diagnose and fix it

  1. Inspect and clean the voltage sense connector and harness at the battery pack for corrosion or damage
  2. Check the voltage sense circuit wiring for continuity, shorts to ground, and shorts to voltage using a multimeter
  3. Verify the battery pack voltage at the sense terminals and compare with the scan tool data to confirm the discrepancy
  4. Perform a visual inspection of the battery pack for signs of coolant leaks, water intrusion, or physical damage
  5. Follow the manufacturer's diagnostic flow chart for circuit B, which may include a resistance check of the sense harness
  6. If the circuit is intact, test or replace the battery energy control module or the internal sense harness as directed by service information
  7. Clear the code and perform a road test or hybrid system self-test to confirm the repair and ensure the code does not return

What the voltage sense circuit really monitors

  • This code often sets intermittently due to a poor connector pin tension that only acts up under vibration or temperature swings, so a wiggle test of the harness while watching live data is essential.
  • A voltage sense fault can be caused by a failing 12-volt auxiliary battery on some hybrids, which corrupts the control module's reference voltage and sets false sense codes.
  • Technicians sometimes replace the entire battery pack when the actual fault is a chafed sense wire behind the pack, so always trace the circuit before condemning the pack.
  • The sense circuit B monitors a specific group of cells, and a single weak module can pull the sensed voltage out of range without setting a performance code for that module.
  • After any repair involving the high-voltage battery, the code may remain stored until the battery control module completes a full self-test cycle, which can require a key-off sleep period.

Can I keep driving with P0B14?

The vehicle may remain drivable in a reduced-power mode, but continued driving risks a sudden loss of hybrid assistance or a no-start condition. Avoid long trips and high-load driving until the fault is diagnosed, and do not attempt to service the high-voltage battery without proper training and personal protective equipment.

Tools that help

Tools we recommend are in the Auto Veteran shop on Amazon. As an Amazon Associate we earn from qualifying purchases.

Guidance is general and written for all OBD-II vehicles. Exact tests and values vary by model, so confirm the fault before replacing parts.

Running on fumes Free guides aren't free to make. Top up the tank. Any amount, one time. Fuel the Garage