C0021 Code - Brake Booster Performance
Quick Answer
When the Vacuum Pressure Sensor indicates a failure in the Vacuum Booster. Common causes include Faulty Brake Booster, Faulty Vacuum Pressure Sensor, Vacuum Pressure Sensor harness is open or shorted. 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
- C0021 indicates Brake Booster Performance.
- Common causes
- Common causes include Faulty Brake Booster, Faulty Vacuum Pressure Sensor, Vacuum Pressure Sensor harness is open or shorted.
- 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 C0021 Description
What are the Possible Causes of the DTC C0021?
- Faulty Brake Booster
- Faulty Vacuum Pressure Sensor
- Vacuum Pressure Sensor harness is open or shorted
- Vacuum Pressure Sensor circuit poor electrical connection
How to Fix the DTC C0021?
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 C0021 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.
Need more information about the C0021 code?
Need more information on how to fix the C0021 code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the C0021 code diagnosed by a professional: Find a repair shop in your area
Information for Specific Makes
- C0021 Buick — Right Front Wheel Speed Sensor Circuit Open Or Shorted To Battery
- C0021 Cadillac — Right Front Wheel Speed Sensor Circuit Open Or Shorted To Battery
- C0021 Chevrolet — Right Front Wheel Speed Sensor Circuit Open Or Shorted To Battery
- C0021 Chrysler — Brake Booster Performance
- C0021 Dodge — Brake Booster Performance
- C0021 GMC — Right Front Wheel Speed Sensor Circuit Open Or Shorted To Battery
- C0021 Jeep — Brake Booster Performance
- C0021 Subaru — Front Right ABS Sensor Circuit Open Or Short
Frequently Asked Questions about C0021 Code
1. What are the common symptoms of OBDII code C0021 (Brake Booster Performance)?
- Common symptoms include a firm brake pedal, difficulty in applying brakes, and potential loss of power brakes.
2. What are the possible causes of OBDII code C0021 (Brake Booster Performance)?
- The code can be triggered by issues such as a faulty brake booster, vacuum leaks, or problems with the brake booster sensor.
3. How can I diagnose the OBDII code C0021 (Brake Booster Performance)?
- Diagnosis typically involves inspecting the brake booster for proper function, checking vacuum lines for leaks, and testing the brake booster sensor.
4. What are the recommended repair options for OBDII code C0021 (Brake Booster Performance)?
- Repair options may include replacing the brake booster, repairing vacuum leaks, or recalibrating the brake booster sensor.
5. Can I continue driving with OBDII code C0021 (Brake Booster Performance) present?
- It is not recommended to drive with this code, as it can affect the performance of your brakes and compromise safety.
6. How much does it cost to repair OBDII code C0021 (Brake Booster Performance)?
- The cost of repair can vary depending on the extent of the issue, but it may range from a couple of hundred dollars to over a thousand dollars.
7. Is OBDII code C0021 (Brake Booster Performance) an urgent issue that needs immediate attention?
- Yes, addressing this code promptly is crucial to ensure the proper functioning of your vehicle's braking system and overall safety.
8. Can OBDII code C0021 (Brake Booster Performance) be triggered by other underlying problems?
- Yes, other issues such as brake fluid leaks, master cylinder problems, or ABS system malfunctions can sometimes trigger this code.
9. How long does it typically take to repair OBDII code C0021 (Brake Booster Performance)?
- The repair time can vary depending on the specific cause of the issue and the availability of parts, but it may take a few hours to a full day.
10. Will resetting the OBDII code C0021 (Brake Booster Performance) temporarily fix the issue?
- Resetting the code may temporarily clear the warning light, but it will not resolve the underlying problem causing the code to appear.
Discuss the causes and fixes for C0021 OBDII Code
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