AutoCodes – Cadillac – C0299 Cadillac

C0299 Cadillac Code - Brake Booster Large Vacuum Leak Detected

Quick Answer

The brake booster vacuum sensor measures the vacuum in the brake booster assembly. Common causes include Vacuum leak at the brake booster, Faulty Brake Booster Vacuum Sensor, Brake Booster Vacuum 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: C0299 Cadillac indicates Brake Booster Large Vacuum Leak Detected.
Common causes: Common causes include Vacuum leak at the brake booster, Faulty Brake Booster Vacuum Sensor, Brake Booster Vacuum 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.

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Code Popularity 6,214

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 Jul 05, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code C0299 Cadillac Description

The brake booster vacuum sensor measures the vacuum in the brake booster assembly. The Electronic Brake Control Module (EBCM) supplies a 5 V reference and a low reference circuit to the brake booster vacuum sensor. The vacuum sensor supplies a voltage signal in relation to the pressure in the brake booster to the Electronic Brake Control Module. The Diagnostic Trouble Code (DTC) will be set when the Electronic Brake Control Module detected a too-low vacuum in the brake booster assembly.

OBDII Code C0299 Cadillac - Brake Booster Large Vacuum Leak Detected - AutoCodes.com — C0299 Cadillac Code - Brake Booster Large Vacuum Leak Detected

What does this mean?

What are the Possible Causes of the DTC C0299 Cadillac?

Vacuum leak at the brake booster
Faulty Brake Booster Vacuum Sensor
Brake Booster Vacuum Sensor harness is open or shorted
Brake Booster Vacuum Sensor circuit poor electrical connection
Faulty Electronic Brake Control Module (EBCM)

How to Fix the DTC C0299 Cadillac?

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 C0299 Cadillac 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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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 C0299 Cadillac Code

1. What does the OBDII code C0299 mean on a Cadillac?

C0299 indicates that the vehicle's brake booster has a large vacuum leak, which can impair the braking system's performance.

2. What are the symptoms of code C0299 in a Cadillac?

Common symptoms include a hard brake pedal, reduced braking performance, hissing noises from the brake booster, and possibly an illuminated ABS or brake warning light.

3. What causes the C0299 code to appear?

The code is typically caused by a damaged or leaking brake booster diaphragm, a cracked vacuum hose, a faulty check valve, or low engine vacuum.

4. Can I drive my Cadillac with a C0299 code?

It is not recommended to drive with this code active, as it may lead to increased stopping distances and compromised braking safety.

5. How do I diagnose the C0299 code on my Cadillac?

Start by inspecting the vacuum hoses and connections for leaks or damage, check the brake booster for audible hissing sounds, and test the check valve for proper operation.

6. How is the C0299 code repaired?

Repairs may involve replacing a damaged vacuum hose, repairing or replacing the brake booster, or replacing a faulty check valve.

7. How much does it cost to fix a C0299 code on a Cadillac?

Repair costs vary depending on the issue but can range from $50 for a vacuum hose replacement to $500 or more for a new brake booster.

8. Can a vacuum leak outside the brake system trigger a C0299 code?

No, this code specifically refers to a vacuum leak affecting the brake booster system.

9. How does a faulty check valve contribute to a C0299 code?

A faulty check valve may fail to maintain proper vacuum pressure in the brake booster, leading to insufficient braking assistance and triggering the code.

10. What tools are needed to diagnose and fix a C0299 code?

Useful tools include a vacuum pump or gauge, a scan tool for reading and clearing codes, and basic hand tools for inspecting and replacing components.