Don't Panic — Diagnose First
A car that won't start is one of the most stressful breakdowns you can experience — especially when you're running late for work or stuck in a car park after hours. The good news? Most no-start situations come down to a handful of common causes, and some of them you can fix on the spot without any tools.
Before you call for roadside assistance, work through these checks in order. They're arranged from the most common (and easiest to fix) to the least common.
7 Things to Check When Your Car Won't Start
1. Is It the Battery?
This is the number one reason cars won't start — by a wide margin. Here's how to tell:
- Turn the key or press the start button. If you hear a slow, laboured crank or a rapid click-click-click, the battery is flat or dying.
- Check if dashboard lights come on. If nothing happens at all — no lights, no sound — it's almost certainly a dead battery or a loose connection.
- Look at the battery terminals under the hood. White or green corrosion on the terminals can prevent the battery from delivering power even if it's fully charged.
Quick fix: If you have jumper cables and another vehicle, you can jumpstart the car. Otherwise, a mobile mechanic can come to you with a replacement battery — Pro Tune carries batteries for most makes and models and services the Northern Beaches and North Shore 24/7.
2. Are You Out of Fuel?
It sounds obvious, but fuel gauges aren't always accurate — especially in older vehicles. If the engine cranks normally (sounds healthy) but just won't fire up, check your fuel level. Some cars will crank endlessly on an empty tank without throwing any warning lights.
3. Is It in Park (or Neutral)?
Automatic vehicles have a neutral safety switch that prevents the engine from starting unless the transmission is in Park or Neutral. If the switch is slightly worn or the shifter isn't fully seated in Park, the car won't start. Try shifting firmly into Park, or try Neutral instead.
Manual cars have a similar system — the clutch interlock switch requires you to fully depress the clutch pedal before starting. Make sure you're pressing it all the way to the floor.
4. Check the Key Fob Battery
If you drive a push-button start vehicle, the car communicates with your key fob wirelessly. When the fob battery dies, the car can't detect it and won't let you start the engine.
Quick fix: Most cars have a backup method — hold the key fob directly against the start button, or look for a hidden physical key slot near the steering column. Your owner's manual will have the exact procedure for your model.
5. Listen for the Fuel Pump
When you turn the key to the "on" position (without cranking), you should hear a quiet hum or whirring sound from the back of the car for about 2 seconds. That's the fuel pump priming. If you hear nothing, the fuel pump may have failed — this requires a mechanic.
6. Check for a Blown Fuse
Your car's fuse box (usually under the dashboard or in the engine bay) contains fuses for critical systems including the fuel pump, ignition, and starter relay. A single blown fuse can prevent the car from starting. Check your owner's manual for the fuse diagram and look for any fuses with a broken filament.
Quick fix: If you find a blown fuse, replace it with one of the same amperage. Most cars come with spare fuses in the fuse box lid. If the new fuse blows immediately, there's an underlying electrical issue that needs professional diagnosis.
7. Is the Starter Motor Failing?
If the battery is good (dashboard lights are bright, accessories work) but you hear a single loud click when you turn the key, the starter motor or starter solenoid may be failing. This is different from the rapid clicking of a flat battery — it's one solid "clunk" followed by silence.
A failing starter can sometimes be temporarily coaxed to life by gently tapping the starter motor housing with a tool handle while someone turns the key. This is a temporary fix only — the starter needs replacing.
Still Won't Start? Here's What to Do
If you've worked through these checks and the car still won't start, it's time to call a professional. The issue could be a faulty ignition switch, a failed crankshaft position sensor, a timing belt failure, or an immobiliser fault — all of which need diagnostic equipment to pinpoint.
The advantage of calling a mobile mechanic is that we come to wherever you are. Whether you're stuck at home in Manly, broken down at Warringah Mall, or stranded in a side street in Cremorne — Pro Tune will come to you, diagnose the problem on the spot, and fix it if possible.
