AutoCodes – Generic – C128A

C128A Code - ABS Boost Pressure Sensor Offset Error

Quick Answer

The Electronic Brake Control Module (EBCM) uses input from the boost pressure sensor for more accurate control during brake and vehicle stability enhancement system event. Common causes include Faulty Brake Pressure Modulator, Brake Pressure Modulator harness is open or shorted, Brake Pressure Modulator circuit poor electrical connection. 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: C128A indicates ABS Boost Pressure Sensor Offset Error.
Common causes: Common causes include Faulty Brake Pressure Modulator, Brake Pressure Modulator harness is open or shorted, Brake Pressure Modulator circuit poor electrical connection.
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 1,364

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 Sep 03, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code C128A Description

The Electronic Brake Control Module (EBCM) uses input from the boost pressure sensor for more accurate control during brake and vehicle stability enhancement system event. The boost pressure sensor is internal to the brake pressure modulator.

OBDII Code C128A - ABS Boost Pressure Sensor Offset Error - AutoCodes.com — C128A Code - ABS Boost Pressure Sensor Offset Error

What does this mean?

What are the Possible Causes of the DTC C128A?

Faulty Brake Pressure Modulator
Brake Pressure Modulator harness is open or shorted
Brake Pressure Modulator circuit poor electrical connection

How to Fix the DTC C128A?

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 C128A 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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Need Help with the Code?

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Information for Specific Makes

C128A Buick — ABS Boost Pressure Sensor Offset Error
C128A Cadillac — ABS Boost Pressure Sensor Offset Error
C128A Chevrolet — ABS Boost Pressure Sensor Offset Error
C128A GMC — ABS Boost Pressure Sensor Offset Error

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 C128A Code

1. What are the common symptoms of OBDII code C128A (ABS Boost Pressure Sensor Offset Error)?

The common symptoms include the ABS warning light illuminated on the dashboard, decreased braking performance, and potential traction control issues.

2. What could be the possible causes of OBDII code C128A?

Possible causes of this code include a faulty ABS boost pressure sensor, wiring issues or damage in the ABS system, or a malfunction in the ABS control module.

3. How can I diagnose OBDII code C128A at home?

You can diagnose this code using an OBDII scanner to read the error code and identify the specific issue with the ABS boost pressure sensor. Additionally, a visual inspection of the sensor and its wiring can help identify any visible damage.

4. Can I continue driving with OBDII code C128A present?

It is not recommended to continue driving with this code present, as it can affect the proper functioning of your ABS system and compromise your vehicle's safety.

5. How can I repair OBDII code C128A (ABS Boost Pressure Sensor Offset Error)?

Repairing this code typically involves replacing the faulty ABS boost pressure sensor or addressing any wiring issues in the ABS system. It is recommended to consult a professional mechanic for an accurate diagnosis and repair.

6. Are there any DIY tips for fixing OBDII code C128A?

While some may attempt to replace the ABS boost pressure sensor themselves, it is important to have the proper tools and knowledge to ensure a successful repair. Consulting a professional mechanic is always the safest option.

7. How much does it cost to repair OBDII code C128A?

The cost of repairing this code can vary depending on the specific issue causing the error, the make and model of your vehicle, and labor costs. It is best to get a few quotes from mechanics to determine the cost.

8. Can OBDII code C128A be triggered by a loose gas cap?

No, OBDII code C128A specifically relates to an ABS boost pressure sensor offset error and is not related to a loose gas cap.