Stopped on the road? Sort out where you are before the car
If the car died in traffic or on a freeway, put the hazard lights on and get everyone out on the side away from the cars, behind a barrier if there is one. Don't stand between the car and the traffic, and don't try to fix anything there. Call roadside assistance if you have it. If anyone is hurt or in danger, call 000.
What does the car do when you turn the key?
| What it usually points to | What to try | |
|---|---|---|
| Nothing, and the dash is dead | A flat battery, or a loose or corroded battery connection. | Check the lights. A jump start if the manual allows it. |
| A rapid clicking, dim lights | The NRMA says this is most likely the battery: there's enough power to click, not enough to turn the engine. | Jump start, then get the battery tested. |
| One loud click, bright lights | The battery looks fine, so the starter motor, its solenoid or its wiring comes next. | Try once or twice more, then call it in. |
| Slow, tired cranking | A battery on its way out, or a starter dragging. RACQ says a sluggish start is usually a discharged battery. | Get the battery tested before it strands you. |
| Strong crank, won't fire | Fuel, ignition or a sensor. RAC WA also lists fuses, spark plugs, leads and an empty tank. | Check the fuel gauge, then stop cranking. |
| Starts, then cuts out | Fuel supply, a sensor, or the car's security system. | Leave it and tell the mechanic what it did. |
Why won't my car turn over?
"Turn over" means the engine spins when you try to start it. If it doesn't, the fault is almost always in the electrical path: battery, cables, or the starter motor. The starter is a small electric motor with a solenoid on it. When you turn the key, the solenoid pushes a little gear into the big toothed ring on the engine's flywheel and sends heavy current to the motor to spin it.
That's why a click matters. It's the solenoid moving. If the engine doesn't spin after the click, either the power isn't there or the motor isn't using it. A good battery test sorts those two out in minutes, which is why it comes first.
RACV says a standard lead-acid battery usually lasts three to five years, and that drives under 20 minutes don't give it much recharging time. If everything points to the battery, go to flat or dead battery.
What to check, in this order
Is it in park or neutral, with the brake on?
Automatics won't start in gear, and manuals usually want the clutch all the way down. A push-button car usually wants your foot on the brake.
Try the spare key
If the key fob battery has gone or the car doesn't recognise the key, the immobiliser (the anti-theft system) can stop the engine. Your owner's manual will say how to start with a flat fob.
Look at the fuel gauge
It catches people out. On a steep slope, a low tank can also starve the pump.
Look at the battery terminals
With everything off, look for white or green corrosion or a loose clamp. If the case is cracked, swollen or leaking, don't touch it.
Stop after a few tries
Long cranking drains a weak battery and heats the starter. Three or four short tries is plenty.
Is it safe to jump start it?
Usually, if you follow the owner's manual. The NRMA warns against it if the battery is cracked or leaking acid, and says jump starting a modern car can cause other problems. Hybrids and electric cars have their own rules. If you're unsure, leave it to roadside assistance or a mechanic.
If it does start, RACV says to drive for 10 to 20 minutes. That only gets you home or to a mechanic. It doesn't fully recharge the battery, and RACQ says a full charge can take up to 24 hours on a charger.
What the mechanic will do
They'll test the battery under load, check the connections and earth straps, then test the charging system, because a flat battery is sometimes an alternator problem in disguise. If power is fine, they'll check voltage at the starter. If the engine cranks but won't fire, they'll check for spark, fuel pressure and stored fault codes.
A mobile mechanic can do most of that where the car sits, including a battery swap, and on many cars a starter. If the starter is buried under the engine, the car may need towing. Ask for a written estimate either way, and ask to see the test result that points to the part. A starter replaced on a hunch is a poor outcome if it was the battery cable all along. For a fault that comes and goes, look for a mechanic who does a lot of electrical work.
What you can do, and what's the mechanic's job
You can
- Check the gear selector, fuel gauge and spare key.
- Look at the battery terminals with everything off.
Leave to the mechanic
- Testing the battery, alternator and starter circuit.
- Replacing a starter or tracing a wiring fault.
If it were our car
We'd check the gauge, try the spare key and try a jump start if the manual says it's fine. If it starts, we'd drive straight to a mechanic for a battery and charging test, not home. If it doesn't, we'd leave it where it is, put "can't be moved" in the note on the card, and let the mechanic decide whether it's a mobile job or a tow.