What the car does when you turn the key tells you most of what you need to know. Clicking or a slow, weak turn almost always means a flat or failing battery. An engine that turns over normally but will not catch points to fuel, spark or air. Complete silence is usually a battery, a connection or the starter.
Here is how to read each symptom, and what to try safely before you call anyone.
A rapid clicking, or a slow, laboured turn
This is the classic flat battery. The dash lights usually dim or flicker when you try. Check the battery terminals are tight and clean, and if you have jump leads or a booster pack and know how to use them safely, try that. If it starts, have the battery and charging system tested, because it will happen again. See how long a car battery lasts.
A single click, then nothing
That can be a flat battery, but also the starter motor or its connection. A starter that is failing will often work on some days and not others. This one needs a garage.
The engine turns over but will not start
- Fuel: is there actually fuel in the tank? Do not trust the gauge if the car is old.
- A faulty sensor, such as the crankshaft sensor, which is a common cause of cranking but not firing.
- Spark and ignition problems on a petrol car.
- Glow plugs on a diesel, mostly in cold weather.
- Immobiliser trouble, usually with a security light flashing on the dash.
Nothing at all
No lights, no clicks. Look at the battery terminals and earth strap for looseness or corrosion. If the key fob is keyless, try the spare, or the fob's emergency method in the handbook, because a flat fob battery will do this.
Before you call for help
- Make sure the car is in park or neutral, and the clutch is pressed on a manual.
- Check the fuel gauge, and look for the security or immobiliser light.
- Try the spare key or fob.
- Do not keep cranking for long, as that can flatten the battery and damage the starter.
- If you smell fuel or see smoke, stop and get help.
Quick answers
Why does my car click but not start?
Clicking nearly always means the battery is too weak to turn the engine. It can also be the starter motor or a poor connection.
Why does my car turn over but not start?
The engine is turning, so the battery is probably fine. The usual causes are fuel, spark or a failed sensor.
Can a jump start damage my car?
Done wrongly it can damage the electronics. Follow your handbook, and do not jump start a hybrid or EV unless it says you can.
Can you recover a car that will not start?
Call us on 01296 706969 and we will advise. If it needs recovering, we can talk you through the options.