The short answer
Listen to what happens when you turn the key. Clicking points to the battery or the starter. An engine that cranks but will not catch has a fuel or spark problem. Total silence with no dash lights is a dead battery or a bad connection.
Rapid clicking
A fast tick-tick-tick means the starter is trying to engage but the battery cannot supply enough power. This is the classic weak battery, and it is most common on the first cold mornings of the year.
A boost will usually get it going. If it does, have the battery and the charging system tested before you trust it again, because a battery that went flat once will do it again.
One loud click, then nothing
A single clunk with no cranking can still be a weak battery, but it also points to a corroded battery terminal or a starter that is on its way out. If the dash lights stay bright while it clicks, the starter is the stronger suspect.
It cranks normally but will not start
If the engine turns over at its usual speed, the battery and starter are doing their job. What is missing is fuel or spark. Common causes are a failed fuel pump, a crankshaft position sensor, an ignition fault or an immobilizer that does not recognise the key.
This one needs a diagnostic. Cranking it over and over will only flatten the battery.
Nothing at all, and no dash lights
No lights, no click, no sound: the battery is completely dead or it is not connected. Look at the battery terminals. A loose clamp or a crust of white or green corrosion can cut the power completely.
It starts and then dies
An engine that fires and stalls within a few seconds is getting something wrong with its air, fuel or sensor readings. It can also be the anti-theft system shutting the engine down. A scan for stored codes is the place to start.
What to try before you call
- Make sure the car is in Park or Neutral with your foot firmly on the brake.
- On a push-button car, hold the key fob right against the start button. A fob with a dead battery can often still be read that way.
- Turn on the headlights. Bright lights that dim when you try to start point to the battery.
- Try a boost. If it starts, drive it to a shop for a test and do not switch it off on the way.
When to stop trying
Do not crank for more than about ten seconds at a time, and give the starter a rest between attempts. If you smell fuel, stop. Call us, describe what it does when you turn the key, and we can usually tell you what to expect before the car even arrives.
Want us to look at it?
Call or text GTS Auto Repair and tell us what the car is doing. We are at 133 Manville Rd, Unit 32, Scarborough, ON M1L 4J7.
