Have you seen the Malfunction Indicator Light (MIL) illuminated with code P25A2? This possibly indicates a problem with the Brake System Control Module (BSCM) or the brake system.
These are essential parts of your car, and a problem with them can be dangerous. Therefore, it is crucial to understand what the code P25A2 means and what you should do if you see it.
In this article, I’ll explain what the code means, discuss the possible causes, and share my advice on what you should do.
So, read on to learn more!
P25A2 Code: An Overview
The P25A2 code can be a bit confusing, but here’s a breakdown of it:
- Definition: Brake System Control Module Requested MIL Illumination
- Severity: Medium
- DIY Skill Level: Advanced
- Continue To Drive?: Yes
- Estimated Repair Cost: $50 – $200
What Does The P25A2 Code Mean?
The P25A2 code is a generic diagnostic trouble code (DTC) defined as “Brake System Control Module Requested MIL Illumination.” This code is not specific to any particular vehicle make or model, but it is commonly triggered in GM vehicles such as the Chevy Silverado, Volt, Corvette, and GMC Sierra.
This DTC suggests that there is a fault or malfunction detected within the brake system control module, which has triggered the module to request the illumination of the MIL. The brake system control module monitors and controls various aspects of the vehicle’s braking system, including ABS (Anti-lock Braking System) and traction control.
When a fault or malfunction is detected within the brake system, such as a sensor reading out of range or a valve not functioning as expected, the brake system control module may set the P25A2 code and request the illumination of the MIL.
The P25A2 code is often associated with other codes which further clarify the issue, such as:
- P0606: PCM / ECM Processor Fault
- C0021: Brake Booster Performance (Subfault)
- C05D2: Brake Master Cylinder Piston Excessive Travel Detected
- U0139: Lost Communication with Suspension Control Module “B”
How Serious Is The P25A2 Code?
When it comes to the severity level of the P25A2 code, it is generally considered medium. In general, the code doesn’t necessarily pose an immediate danger to your vehicle or a complete failure of the braking system.

(Image credit: Corvette Forum)
Despite the code being present, it is generally safe to continue driving. However, to ensure the continued safe operation of your vehicle, having your car inspected and diagnosed by a qualified mechanic at your earliest convenience is recommended.
Read more: GM OBD2 Codes List For FREE Download [Generic + Manufacturer-specific]
Warning Signs Of The P25A2 Code
The P25A2 code may manifest through various symptoms, including:
- Illumination of the check engine light and/or ABS warning light
- Brake system performance issues
Possible Causes Of The P25A2 Code
The code P25A2 can be triggered by several potential causes, such as:
- Malfunctioning brake pedal position sensor
- Faulty wheel speed sensors
- Problem with the brake system wiring
- Wiring or connection issues within the BSCM
- BSCM’s software glitch
- Faulty BSCM
Read more: C0035 Code: Understanding Wheel Speed Sensor Issues
What to Do If You See The P25A2 Code?
As a mechanic, I strongly recommend that you seek professional help if you encounter the P25A2 code. Additionally, it is important to refrain from attempting to fix the code yourself, as it can be a complex situation, particularly for a DIY-er.
There are a few reasons why it is important to take your car to a qualified mechanic or ask for help from your nearest car dealer:
- The P25A2 code often appears associated with other codes, making it difficult to diagnose and fix on your own.
- There are many technical service bulletins (TSBs) related to this code, which your car may be covered by. For example, in 2020, GM had a TSB called PIT5735D to address the P25A2 code associated with U0422, U0420, U0151, and other complex U-codes. A mechanic can apply the TSB and recommend the best action to fix your car.
- The BSCM is a critical safety component, and it is important to have it repaired by a qualified mechanic with the proper tools and knowledge.
Additionally, some of the repairs that may be needed to fix the P25A2 code include:
- Updating the software
- Repair wiring issues
- Repairing or replacing a faulty braking-related components (wheel speed sensor, brake actuator, brake line, etc)
- Replace the BSCM
Final Thoughts
To wrap up, understanding the P25A2 code and its impact on your vehicle’s brake system is crucial for maintaining safety on the road. While it is a medium severity code, we recommend seeking professional assistance by taking your car to an authorized dealer or qualified mechanic. They have the expertise and resources to diagnose and address the issue.
We hope this article has helped you understand the P25A2 code. If you found this information helpful, please share it with others who may benefit. Feel free to leave a comment below to share your experiences or ask any questions.
Happy driving!
Reference Sources
How a Car Works, How the braking system works.