P0B42 Code - Hybrid/Electric Vehicle Battery 2 Circuit Low Voltage
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
- P0B42 indicates Hybrid/Electric Vehicle Battery 2 Circuit Low Voltage.
- 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.
Code P0B42 Description
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.
What are the Possible Causes of the DTC P0B42?
- Faulty Hybrid/Electric Vehicle Battery Pack
- Faulty Hybrid/Electric Vehicle Battery Interface Control Module
How to Fix the DTC P0B42?
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 P0B42 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
- P0B42 Buick — Hybrid/Electric Vehicle Battery 2 Circuit Low Voltage
- P0B42 Cadillac — Hybrid/Electric Vehicle Battery 2 Circuit Low Voltage
- P0B42 Chevrolet — Hybrid/Electric Vehicle Battery 2 Circuit Low Voltage
- P0B42 GMC — Hybrid/Electric Vehicle Battery 2 Circuit Low Voltage
- P0B42 Lexus — Hybrid Battery Voltage Sense 'B' Circuit Low
- P0B42 Nissan — Hybrid Battery Voltage Sense 'B' Circuit Low
- P0B42 Saturn — Hybrid/Electric Vehicle Battery 2 Circuit Low Voltage
- P0B42 Toyota — Hybrid Battery Voltage Sense 'B' Circuit Low
Frequently Asked Questions about P0B42 Code
What does OBDII code P0B42 mean?
Code P0B42 indicates that the Hybrid/Electric Vehicle Battery 2 circuit is experiencing low voltage, which can affect the vehicle's performance and battery management system.
What are the common symptoms of code P0B42?
Symptoms include reduced fuel efficiency, limited hybrid or electric mode functionality, warning lights on the dashboard, and possible difficulty starting the vehicle.
What causes the P0B42 code to appear?
Common causes include a faulty battery module, corroded or damaged wiring, issues with the battery control module, or poor electrical connections in the circuit.
Can I drive my car with the P0B42 code?
It’s not recommended to drive the vehicle for extended periods with this code, as it may lead to reduced performance or further damage to the hybrid battery system.
How is code P0B42 diagnosed?
A technician will use a diagnostic scanner to verify the code and inspect the hybrid battery, wiring, and control module for faults. Voltage tests may be performed on the affected circuit.
How do you fix the P0B42 code?
Repairs may include replacing damaged wiring, repairing or replacing the hybrid battery module, or recalibrating the battery control module.
Can a weak hybrid battery cause code P0B42?
Yes, a degraded or failing hybrid battery can cause low voltage in the affected circuit, triggering this code.
Does the P0B42 code always mean the battery needs replacement?
Not necessarily. The issue could be related to wiring, connectors, or the control module instead of the battery itself.
How much does it cost to repair code P0B42?
Repair costs vary widely depending on the issue, ranging from $150 for wiring repairs to over $3,000 for hybrid battery replacement.
Will clearing the code solve the problem?
Clearing the code may temporarily remove the warning, but the underlying issue must be addressed to prevent the code from returning.
Discuss the causes and fixes for P0B42 OBDII Code
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