Failure Analysis

Step 4 of 7 - AIAG-VDA FMEA

Failure Mode Analysis

Function	Failure Mode	Failure Effects	Failure Causes	Severity	Status
Convert mechanical force to hydraulic pressure FUNC-1011-01	Insufficient pressure generation	Increased stopping distance, potential accident	Worn internal seals, air in system	9	Completed
Convert mechanical force to hydraulic pressure FUNC-1011-01	Pressure loss during application	Brake fade, reduced braking effectiveness	Internal leak, seal deterioration	8	In Review
Maintain pressure seal integrity FUNC-1011-03	External fluid leakage	Fluid loss, brake system failure	Damaged housing, cracked seals	10	Completed
Receive brake fluid from reservoir FUNC-1011-02	Restricted fluid intake	Slow brake response, incomplete brake release	Clogged inlet port, contaminated fluid	6	Draft
Supply brake fluid to master cylinder FUNC-1013-01	Fluid contamination	Degraded brake performance, component damage	Improper fluid, cap seal failure	7	In Review
Receive hydraulic pressure from master cylinder FUNC-1012-01	Brake line rupture	Complete loss of braking to affected wheels	Corrosion, physical damage, excessive pressure	10	Completed

Failure Mode Distribution

Overview of failure modes by severity and component.

Severity Distribution

Failure Modes by Component

High Severity Failure Modes

Critical failure modes requiring immediate attention (Severity 8-10).

Critical Failure Modes

External fluid leakage

Master Cylinder

Fluid loss leading to complete brake system failure. Caused by damaged housing or cracked seals.

Brake line rupture

Brake Lines

Complete loss of braking to affected wheels. Caused by corrosion, physical damage, or excessive pressure.

Insufficient pressure generation

Master Cylinder

Increased stopping distance, potential accident. Caused by worn internal seals or air in system.

Pressure loss during application

Master Cylinder

Brake fade, reduced braking effectiveness. Caused by internal leak or seal deterioration.

Failure Mode Details

Master Cylinder

COMP-1011

Associated Function:

Convert mechanical force to hydraulic pressure (FUNC-1011-01)

Failure Mode Information

Failure Mode

Failure Effects

Local Effects:

System Effects:

Potential Causes

Severity Rating (S) *

Low Medium High

Occurrence Rating (O) *

Remote Moderate High

Detection Rating (D) *

High Moderate Low

Action Priority Level

Based on S, O, D ratings

Medium

Current Prevention Controls

Safety Critical Failure

Detection Methods

Pressure testing

Visual inspection

Notes

AIAG-VDA FMEA Process

Step 1: Planning & Preparation

Define scope, assemble team, and prepare for FMEA

Step 2: Structure Analysis

Identify and analyze system structure and components

Step 3: Function Analysis

Define functions of components and system

Step 4: Failure Analysis

Identify potential failure modes and effects

Step 5: Risk Analysis

Evaluate severity, occurrence, and detection

Step 6: Optimization

Define actions to reduce risk

Step 7: Documentation

Document results and prepare final report

Severity Rating Guide

Hazardous without warning

Failure could cause injury or death without warning

Hazardous with warning

Failure could cause injury with warning

Very High

System inoperable with loss of primary function

High

System performance severely affected

Moderate

System performance affected with reduced function

None

No noticeable effect on system performance