Safety

Working on your car safely

Last updated: 8 July 2026

Working on your own car is easy enough to learn. But a car weighs well over a ton, gets hot, and is partly under tension and pressure. These rules always apply, for every job, however small.

The golden rules

• Secure the car: handbrake on, gear in first (or P), wheel chocks behind the wheels staying on the ground. Only then jack it up, and set it on axle stands.
• Let the engine cool down. The cooling system is pressurised: opening a hot coolant cap means burns. The exhaust and brake discs stay hot for a long time.
• Disconnect the battery for electrical work, negative terminal off first, reconnect it last. That way you avoid short circuits and sparks.
• Fuel and fumes: work in a ventilated space, never with open flame or sparks nearby. Never let an engine run in an enclosed space.
• Protect yourself: gloves and safety glasses aren't an excessive luxury, especially when working overhead, with fluids, or with springs under tension.
• Use the right tools and re-torque wheel bolts with a torque wrench to the specified setting.
• After working on the brakes: pump the brake pedal until it has pressure, and test it calmly in an empty, safe spot before you head onto the road.

Leave this to the garage

Some systems aren't DIY work, either because they're dangerous or because the law requires certification for them:

• Airbags and seatbelt pretensioners. They contain explosive charges.
• Air conditioning. Working on the refrigerant circuit is only allowed with an F-gas certificate.
• High-voltage system of hybrids and EVs. Stay away from anything with orange cables, hundreds of volts run through them.
• Pressurised fuel lines and LPG systems.

How the app helps you with this

Every likely cause gets an honest difficulty level: easy, medium or garage work. At every step you see what tools you need. And if a job is too risky or too complex, we'll just say so, that's exactly what the app is for.

This page is general information, not a complete safety instruction for every job. Always follow the guidance in the step-by-step plan and your car's documentation.