U120C Code - Lost Brake Booster Signal
Quick Answer
The Diagnostic Trouble Code (DTC) sets when the Powertrain Control Module (PCM) doesn't receive a brake booster vacuum signal from the Anti-lock Brake System (ABS) Module over the Controller Area Network (CAN) C bus. Common causes include Faulty Brake Booster Pressure Sensor, Brake Booster Pressure Sensor harness is open or shorted, Brake Booster Pressure 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
- U120C indicates Lost Brake Booster Signal.
- Common causes
- Common causes include Faulty Brake Booster Pressure Sensor, Brake Booster Pressure Sensor harness is open or shorted, Brake Booster Pressure 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 U120C Description
What are the Possible Causes of the DTC U120C?
- Faulty Brake Booster Pressure Sensor
- Brake Booster Pressure Sensor harness is open or shorted
- Brake Booster Pressure Sensor circuit poor electrical connection
- Faulty Anti-lock Brake System (ABS) Module
How to Fix the DTC U120C?
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 U120C 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
- U120C Chrysler — Lost Brake Booster Signal
- U120C Dodge — Lost Brake Booster Signal
- U120C Jeep — Lost Brake Booster Signal
- U120C RAM — Lost Brake Booster Signal
Frequently Asked Questions about U120C Code
1. What are the common symptoms of OBDII code U120C (Lost Brake Booster Signal)?
Symptoms of U120C may include the brake pedal feeling stiff or hard to press, the brake system warning light illuminated on the dashboard, and potential issues with brake performance.
2. What can cause the OBDII code U120C (Lost Brake Booster Signal) to occur?
This code is often triggered by a faulty brake booster sensor, a loose or damaged wiring connection, or issues with the brake booster itself.
3. How can I diagnose the OBDII code U120C (Lost Brake Booster Signal)?
Diagnosing U120C typically involves using a diagnostic scanner to read the code, checking the brake booster sensor and its wiring for any visible damage, and conducting a thorough inspection of the brake booster system.
4. Can driving with the OBDII code U120C (Lost Brake Booster Signal) cause further damage to the vehicle?
Continuing to drive with U120C present can potentially compromise brake performance and safety. It is recommended to address this issue promptly to avoid any safety risks.
5. How can I repair the OBDII code U120C (Lost Brake Booster Signal)?
Repairing U120C may involve replacing the faulty brake booster sensor, repairing any damaged wiring connections, or addressing issues with the brake booster itself. It is advisable to consult a professional mechanic for proper diagnosis and repair.
6. Is it safe to continue driving with the OBDII code U120C (Lost Brake Booster Signal) if the brakes feel normal?
Even if the brakes feel normal, it is not recommended to ignore U120C as it can lead to potential brake system failures. It's best to address the underlying issue promptly to ensure safe operation of the vehicle.
7. Can a DIY enthusiast fix the OBDII code U120C (Lost Brake Booster Signal) at home?
While some DIY enthusiasts may have the necessary skills to address U120C, it is a critical safety issue related to the brake system. It is generally recommended to seek professional assistance to ensure proper diagnosis and repair.
8. How long does it typically take to repair the OBDII code U120C (Lost Brake Booster Signal)?
The repair time for U120C can vary depending on the underlying cause and the extent of the issue. It may take a few hours to a day to diagnose and repair the problem properly.
9. Are there any preventative measures to avoid the OBDII code U120C (Lost Brake Booster Signal) from occurring?
Regular maintenance of the brake system, including checking for any signs of wear or damage, can help prevent issues that may trigger U120C. Promptly addressing any brake-related symptoms can also help avoid this code.
10. Can a low brake fluid level cause the OBDII code U120C (Lost Brake Booster Signal) to appear?
A low brake fluid level is not a direct cause of U120C, but it can lead to other brake system issues that may trigger this code. It's essential to maintain proper brake fluid levels and address any leaks or malfunctions promptly to prevent related problems.
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