🚘 Introduction
Not all FMEAs are created equal.
A DFMEA for an electric vehicle battery looks nothing like a PFMEA for a robotic welding cell. And an FMEA for an embedded control unit? That introduces software failure modes, timing issues, and interface complexity.
In this post, we explore real-world FMEA use cases across four critical domains in the automotive industry:
- Electric Vehicles (EVs)
- Welding Processes
- Electronic Components
- Embedded Software Systems
If you’re working in any of these areas, this guide will help you apply FMEA with the right lens.
⚡ 1. FMEA for Electric Vehicles (EVs)
EVs come with high-voltage, high-risk components—and new types of failures that traditional FMEAs weren’t designed for.
🧩 Key Components:
- Battery Pack
- Inverter
- Electric Drive Unit (Motor + Gearbox)
- On-Board Charger
- HV Cables & Connectors
🧠 Typical DFMEA Failure Modes:
| Component | Failure Mode | Effects |
|---|---|---|
| Battery | Cell overcharge | Thermal event / fire |
| Inverter | Power loss | Loss of propulsion |
| Drive Unit | Gear misalignment | Noise, vibration, premature wear |
💡 PFMEA Considerations:
- Torque accuracy of HV bolts
- Sealant application at connectors
- Thermal paste uniformity
- Cooling system process integrity
✅ Use ASIL classification, pass-through characteristics (PTCs), and functional safety linkages for critical EV subsystems.
🔩 2. FMEA for Welding Processes
Welding operations—whether MIG, TIG, Spot, or Laser—have unique challenges related to joint integrity, thermal distortion, and operator/machine variation.
🧠 PFMEA Use Case:
| Step | Example |
|---|---|
| Process Step | Robotic Spot Welding |
| Function | Create structural joint |
| Failure Mode | Nugget under-diameter |
| Cause | Electrode wear / current drop |
| Effect | Weak joint / crash failure |
| Detection Control | Destructive weld testing (sampling) |
| Prevention | Tip dressing / force monitoring |
💡 Include control limits, electrode maintenance schedules, and operator error-proofing in your prevention/detection strategies.
📟 3. FMEA for Electronic Components (ECUs, Sensors)
Electronic modules are critical to vehicle functionality—and require analysis across hardware design, signal integrity, and EMC performance.
🔧 DFMEA Use Cases:
| Component | Failure Mode | Effect |
|---|---|---|
| Sensor | Signal drift | False detection |
| ECU | PCB short | Loss of control function |
| Connector | Pin corrosion | Signal loss |
📋 Additional Focus:
- Environmental conditions (vibration, temperature, moisture)
- Voltage range validation
- Component derating
- Field failure history
✅ Consider linking DFMEA with FMEDA and system-level FMEA for full safety coverage.
💻 4. FMEA for Embedded Software & Logic
As vehicles become computers on wheels, software-related failures are invisible but dangerous.
🧠 DFMEA Use Case:
| Function | Failure Mode | Cause |
|---|---|---|
| Brake ECU | Wrong torque request | Timing mismatch |
| BCM | Headlamp doesn’t switch | Logic error in conditions |
| Gateway | CAN timeout | Packet loss / delay |
Key FMEA Elements for Software:
- Function timing (cycle time)
- Input/output dependencies
- Watchdog & fallback logic
- Reset and recovery mechanisms
✅ Pair with interface analysis, use ISO 26262, and ensure cause-effect mapping through signal chains.
🧠 5. How to Adapt FMEA by Domain
| Domain | Adaptation Needed |
|---|---|
| EVs | Safety goals, ASIL linkage, cooling + HV risks |
| Welding | Heat zones, nugget size, PTCs, destructives |
| Electronics | Derating, PCB design, EMC, signal analysis |
| Embedded | Software timing, logical flows, interface chains |
📌 Bonus Tips for Cross-Domain FMEAs
- Include customer field data to enrich failure modes
- Use Modular FMEA for common modules (sensors, weld cells)
- Track reused functions and failure chains using software
- Review FMEAs with specialists from each domain
✅ Summary
| FMEA Should Reflect the Real-World Risks of Your Domain |
|---|
| EVs → High voltage, thermal events, interface complexity |
| Welding → Process variation, quality controls, inspection gaps |
| Electronics → Environmental sensitivity, circuit failure |
| Software → Logical errors, interface faults, timing issues |
Tailor your FMEA approach to your technology—generic FMEAs won’t cut it in modern automotive systems.
📥 Bonus Download:
📄 [4-Domain FMEA Starter Template Pack – EVs, Welding, Electronics, Software] (Insert link)
🔁 Coming Up Next in the Series:
Post #12: Future of FMEA: AI, Automation & Digital Twins
🔗 Internal Links to Add:
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