C12B1 GMC Code - ABS Master Cylinder Pressure Sensor and Brake Pedal Position Sensor Not Plausible
Quick Answer
The Electronic Brake Control Module uses inputs from the Electronic Brake Control Brake Pedal Position Sensor to determine when the brake is applied and how much force is used. Common causes include Faulty Electronic Brake Control Module (EBCM), Electronic Brake Control Module harness is open or shorted, Electronic Brake Control Module 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
- C12B1 GMC indicates ABS Master Cylinder Pressure Sensor and Brake Pedal Position Sensor Not Plausible.
- Common causes
- Common causes include Faulty Electronic Brake Control Module (EBCM), Electronic Brake Control Module harness is open or shorted, Electronic Brake Control Module 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.
Code C12B1 GMC Description
Brake pressure sensor information is communicated from the Electronic Brake Control Module (EBCM) to the Hybrid Control Processor (HCP). This information is used to schedule regenerative braking and engine autostops.
The Diagnostic Trouble Code (DTC) will be set when the Engine Control Module (ECM) detects a corrupted data message from the Electronic Brake Control Module.
What are the Possible Causes of the DTC C12B1 GMC?
- Faulty Electronic Brake Control Module (EBCM)
- Electronic Brake Control Module harness is open or shorted
- Electronic Brake Control Module circuit poor electrical connection
- Faulty Starter/Generator Control Module
How to Fix the DTC C12B1 GMC?
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 C12B1 GMC 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 GMC Models
- C12B1 2014 GMC Sierra — ABS Master Cylinder Pressure Sensor and Brake Pedal Position Sensor Not Plausible
- C12B1 2015 GMC Sierra — ABS Master Cylinder Pressure Sensor and Brake Pedal Position Sensor Not Plausible
- C12B1 2016 GMC Sierra — ABS Master Cylinder Pressure Sensor and Brake Pedal Position Sensor Not Plausible
- C12B1 2017 GMC Sierra — ABS Master Cylinder Pressure Sensor and Brake Pedal Position Sensor Not Plausible
- C12B1 2018 GMC Sierra — ABS Master Cylinder Pressure Sensor and Brake Pedal Position Sensor Not Plausible
Frequently Asked Questions about C12B1 GMC Code
What does the OBDII code C12B1 mean for my GMC vehicle?
C12B1 indicates a problem with the ABS Master Cylinder Pressure Sensor and the Brake Pedal Position Sensor not providing plausible data to the vehicle's computer.
What are common symptoms of the C12B1 code?
Common symptoms include an illuminated ABS warning light, a spongy or unresponsive brake pedal, changes in brake performance, and possible traction control issues.
What could cause the C12B1 code to trigger?
Potential causes include a faulty ABS master cylinder pressure sensor, a malfunctioning brake pedal position sensor, damaged wiring or connectors, or issues with the ABS control module.
How can I diagnose the C12B1 code?
To diagnose C12B1, start by using an OBDII scanner to confirm the code. Inspect the wiring and connectors for damage, test the sensors with a multimeter, and check for any additional codes that may provide more context.
What repairs are needed to fix the C12B1 code?
Repairs may involve replacing the ABS master cylinder pressure sensor or the brake pedal position sensor, fixing any damaged wiring, or reprogramming or replacing the ABS control module if necessary.
Can I drive my GMC with the C12B1 code?
While it may be possible to drive your vehicle, it is not recommended as brake performance may be compromised, leading to potentially dangerous driving conditions.
How do I reset the C12B1 code after repairs?
After addressing the issue, you can reset the C12B1 code by using an OBDII scanner to clear the trouble codes or by disconnecting the vehicle's battery for a short period.
Is the C12B1 code serious?
Yes, the C12B1 code is serious because it can affect your vehicle's braking system, which is crucial for safety. It is advisable to address this issue promptly.
Will clearing the C12B1 code fix the underlying problem?
No, clearing the code will not fix the underlying problem. It is important to diagnose and repair the issue before clearing the code to ensure safe vehicle operation.
What is the cost range for repairing the C12B1 code?
Repair costs can vary widely depending on the specific issue, but you might expect to pay anywhere from $100 to $500 or more, including parts and labor.
Discuss the causes and fixes for C12B1 GMC OBDII Code
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