C129A GMC Code - Brake Pedal Position Sensor 3 Circuit Low Input
Quick Answer
The Electronic Brake Control Module (EBCM) 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 Brake Pedal Position Sensor, Brake Pedal Position Sensor harness is open or shorted, Brake Pedal Position Sensor 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
- C129A GMC indicates Brake Pedal Position Sensor 3 Circuit Low Input.
- Common causes
- Common causes include Faulty Brake Pedal Position Sensor, Brake Pedal Position Sensor harness is open or shorted, Brake Pedal Position Sensor 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 C129A GMC Description
What are the Possible Causes of the DTC C129A GMC?
- Faulty Brake Pedal Position Sensor
- Brake Pedal Position Sensor harness is open or shorted
- Brake Pedal Position Sensor circuit poor electrical connection
- Faulty Electronic Brake Control Module (EBCM)
How to Fix the DTC C129A 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 C129A 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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Frequently Asked Questions about C129A GMC Code
What does OBDII code C129A mean on a GMC vehicle?
C129A indicates a "Brake Pedal Position Sensor 3 Circuit Low Input," meaning the vehicle's brake pedal position sensor is detecting a low voltage signal in Circuit 3.
What are the common symptoms of the C129A code?
Symptoms may include the ABS or traction control warning light turning on, inconsistent brake pedal feedback, and possible loss of certain brake-related functions like hill assist.
What causes the C129A code to appear?
Common causes include a faulty brake pedal position sensor, damaged wiring or connectors in the sensor circuit, or issues with the vehicle's control module.
Can I drive my GMC with the C129A code active?
While the vehicle may still be drivable, it's not recommended as safety systems like ABS or traction control could be compromised.
How do I diagnose the C129A code?
Diagnosis typically involves checking the brake pedal position sensor for proper operation, inspecting the wiring and connectors for damage, and performing voltage tests on Circuit 3.
What tools are needed to fix a C129A code?
You may need an OBDII scanner, a multimeter to test voltage and continuity, and basic hand tools to access and replace the brake pedal position sensor if necessary.
How can I fix the C129A code on my GMC?
Repairs might include replacing the brake pedal position sensor, repairing damaged wiring or connectors, or reprogramming the control module if needed.
What is the brake pedal position sensor's role in a GMC vehicle?
The sensor monitors the position of the brake pedal and sends signals to systems like ABS, traction control, and the engine control module to ensure proper operation.
How much does it cost to repair the C129A code?
Repair costs vary but typically range from $150 to $400 depending on whether the sensor needs replacement or wiring repairs are required.
Can a low battery cause the C129A code to appear?
Yes, a weak or low battery can sometimes cause voltage-related errors, including the C129A code, though this is less common.
Discuss the causes and fixes for C129A GMC OBDII Code
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