AutoCodes – Generic – P1B15

P1B15 Code - Regenerative Braking Torque Request Signal Message Counter Incorrect

Quick Answer

This diagnostic applies to internal microprocessor integrity conditions within the hybrid powertrain control module. Common causes include Reprogram Motor Generator Power Inverter Module, Faulty Motor Generator Power Inverter Module, Motor Generator Power Inverter Module 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: P1B15 indicates Regenerative Braking Torque Request Signal Message Counter Incorrect.
Common causes: Common causes include Reprogram Motor Generator Power Inverter Module, Faulty Motor Generator Power Inverter Module, Motor Generator Power Inverter Module 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 1,695

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 Mar 12, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1B15 Description

This diagnostic applies to internal microprocessor integrity conditions within the hybrid powertrain control module. The hybrid powertrain control module is internal to the power inverter module, often referred to as the drive motor generator power inverter module and is not serviced separately. The hybrid powertrain control module monitors its ability to read and write to the memory. The hybrid powertrain control module processor monitors the data to verify that the indicated brake torque request calculation is correct.

OBDII Code P1B15 - Regenerative Braking Torque Request Signal Message Counter Incorrect - AutoCodes.com — P1B15 Code - Regenerative Braking Torque Request Signal Message Counter Incorrect

What does this mean?

What are the Possible Causes of the DTC P1B15?

Reprogram Motor Generator Power Inverter Module
Faulty Motor Generator Power Inverter Module
Motor Generator Power Inverter Module harness is open or shorted
Motor Generator Power Inverter Module circuit poor electrical connection

How to Fix the DTC P1B15?

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 P1B15 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

P1B15 Buick — Regenerative Braking Torque Request Signal Message Counter Incorrect
P1B15 Cadillac — Regenerative Braking Torque Request Signal Message Counter Incorrect
P1B15 Chevrolet — Regenerative Braking Torque Request Signal Message Counter Incorrect
P1B15 GMC — Regenerative Braking Torque Request Signal Message Counter Incorrect
P1B15 Saturn — Regenerative Braking Torque Request Signal Message Counter Incorrect

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 P1B15 Code

What does the OBDII code P1B15 mean?

The OBDII code P1B15 indicates that there is an incorrect message count for the regenerative braking torque request signal in the vehicle's hybrid or electric system.

What are the common symptoms associated with code P1B15?

Common symptoms include reduced regenerative braking efficiency, warning lights on the dashboard, and in some cases, the vehicle may enter a limp mode to prevent further issues.

What can cause the P1B15 code to trigger?

Causes can include faulty wiring or connectors, issues with the regenerative braking system, a malfunctioning brake control module, or software errors in the vehicle's control systems.

How can I diagnose the P1B15 code?

To diagnose P1B15, you should use an OBDII scanner to confirm the code, check for any related codes, inspect wiring and connectors, and test the regenerative braking system components for proper operation.

What should I do if I see the P1B15 code?

If you see the P1B15 code, start by checking the vehicleâ€™s wiring and connectors for damage. If everything appears fine, further diagnosis of the regenerative braking system may be necessary.

Can I drive my vehicle with the P1B15 code?

While you may be able to drive the vehicle, it is not recommended as the regenerative braking system might not function properly, potentially leading to longer stopping distances and safety concerns.

What repairs are typically needed for code P1B15?

Repairs can vary but may include fixing or replacing damaged wiring, updating or reprogramming the brake control module, or replacing faulty components in the regenerative braking system.

Is there a risk of further damage if I ignore the P1B15 code?

Yes, ignoring the P1B15 code can lead to further issues with the vehicle's braking system, decreased efficiency, and potentially more costly repairs down the line.

How can I prevent the P1B15 code from occurring in the future?

Regular maintenance of the vehicle's electrical systems, including inspecting wiring and connectors, can help prevent issues. Keeping the software up to date with the manufacturerâ€™s recommendations is also beneficial.