AutoCodes – Generic – C1178

C1178 Code - ABS Active Brake Booster

Quick Answer

The Active Brake Booster consists of a vacuum booster, an active booster control group, and a delta stroke sensor. Common causes include Faulty Active Booster (Power Brake Booster), Faulty ABS Control Unit/Actuator, ABS Control Unit/Actuator 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: C1178 indicates ABS Active Brake Booster.
Common causes: Common causes include Faulty Active Booster (Power Brake Booster), Faulty ABS Control Unit/Actuator, ABS Control Unit/Actuator 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 17,158

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

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Table of contents Created and updated by William Orellana on Oct 05, 2023

Description
Possible Causes
How To Fix
Tech Notes ▶
Cost to Diagnose
FAQs
Comments
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Code C1178 Description

The Active Brake Booster consists of a vacuum booster, an active booster control group, and a delta stroke sensor. If a brake booster system malfunction occurs due to loss of vacuum, the delta stroke sensor will signal the ABS actuator and electric unit (control unit) that a booster malfunction has occurred. The active booster then applies supplemental force to the master cylinder relative to the amount of force exerted on the brake pedal. The Diagnostic Trouble Code (DTC) will be set when the Active Booster Solenoid is malfunctioning, or the signal line of the active booster servo is open or shorted.

OBDII Code C1178 - ABS Active Brake Booster - AutoCodes.com — C1178 Code - ABS Active Brake Booster

What does this mean?

What are the Possible Causes of the DTC C1178?

Faulty Active Booster (Power Brake Booster)
Faulty ABS Control Unit/Actuator
ABS Control Unit/Actuator harness is open or shorted
ABS Control Unit/Actuator circuit poor electrical connection

How to Fix the DTC C1178?

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 does this mean?

Code Tech Notes

User Submitted Video

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the C1178 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 C1178 code?

Need more information on how to fix the C1178 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the C1178 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

C1178 Infiniti — ABS Active Brake Booster
C1178 Mazda — Left Rear ABS Wheel Speed Sensor/Sensor Rotor
C1178 Mercedes-Benz — Steering Angle Sensor Steering Angle Not Initialize
C1178 Nissan — ABS Active Brake Booster

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 C1178 Code

1. What does OBDII code C1178 mean?

C1178 indicates an issue with the ABS Active Brake Booster system, which affects the vehicle's ability to properly regulate braking pressure.

2. What are common symptoms of code C1178?

Common symptoms include the ABS warning light illuminating, reduced braking performance, or the brake pedal feeling stiff or unresponsive.

3. What causes the C1178 code to appear?

This code is typically caused by a malfunctioning brake booster, a faulty ABS module, damaged wiring or connectors, or low brake fluid levels.

4. Can I still drive with a C1178 code?

Driving with this code is not recommended as it may compromise braking performance, increasing the risk of an accident.

5. How is code C1178 diagnosed?

A mechanic will use a scan tool to confirm the code, inspect the brake booster, wiring, and ABS system components, and check for brake fluid leaks or low levels.

6. How do I fix the C1178 code?

Repairs may involve replacing the brake booster, repairing damaged wiring, replacing the ABS module, or refilling and bleeding the brake fluid.

7. What tools are needed to address a C1178 code?

A diagnostic scan tool, basic hand tools, a multimeter for electrical testing, and potentially a brake fluid bleeding kit may be required for repairs.

8. How much does it cost to fix code C1178?

Repair costs vary but may range from $200 to $1,000 depending on the parts that need replacement, such as the brake booster or ABS module.

9. Can low brake fluid cause code C1178?

Yes, low or contaminated brake fluid can trigger this code by impairing the function of the ABS system and brake booster.

10. How can I prevent code C1178 from occurring?

Regularly inspect and maintain the brake system, including checking brake fluid levels, inspecting wiring, and addressing any ABS warning lights promptly.