Listen to what happens when you turn the key
The noise (or lack of it) tells you almost everything. Find your case:
Nothing lights up at all
Dashboard dark, not a click. Most likely a completely flat battery or a disconnected/corroded terminal.
A rapid "click-click-click"
The starter tries but doesn't have enough current. A typical weak battery, especially in cold weather.
A single sharp "click", then nothing
The solenoid clicks but the engine doesn't turn: often a starter at the end of its life (or a very weak battery).
It starts, then stalls
The engine starts then dies, with the red battery light on while driving: suspect the alternator, which has stopped charging.
The headlight test in 10 seconds
A free test that already rules out half the possibilities: switch the ignition on (without starting) and turn on the headlights.
- Headlights very dim or off → flat battery, almost certainly.
- Headlights bright but the starter won't crank → battery OK, look at the starter or ignition switch.
- Headlights dim sharply when you turn the key → weak battery, nearly finished.
Cold-weather tip. In winter, a slightly tired battery loses up to 30% of its capacity. Many December “breakdowns” are just 5-year-old batteries that can't cope with the cold anymore. It's not the starter motor.
Battery, alternator, starter: how to tell them apart
Jump-starting: yes, but…
A jump start from another car often confirms the diagnosis: if the car starts and runs fine, it was the battery. If it stalls as soon as you disconnect, the alternator isn't charging. But be careful: on recent vehicles (start-stop, lots of electronics), connecting the cables wrongly can damage expensive ECUs. If in doubt, have a mechanic do a multimeter test.
The "blind replacement" trap. Changing a battery when the real culprit is the alternator means paying twice: the new battery will go flat in turn. That's why it's worth testing the battery AND the alternator before replacing anything.
What we do when we come to you
The Warehouse Care mechanic comes to wherever the car is stuck. He tests the battery (voltage, cranking capacity) and the alternator (charging while running), and only then draws a conclusion. If it's the battery, he replaces it on the spot with one suited to your vehicle, with the electronic coding needed on start-stop cars, and takes the old one away for recycling. You're back on the road straight away.
Frequently asked questions
How can you tell if it's the battery or the starter?
Turn the headlights on with the ignition on. If they're dim, it's the battery. If they're bright but the starter won't turn the engine (a single sharp "click"), it's more likely the starter. A jump start that holds confirms the battery.
Can a battery die overnight?
Yes, especially after 4-5 years or a cold snap. It gradually loses capacity, then one morning it can't start the car. It's the most common breakdown.
Do you come out if my car won't start at all?
Yes: Warehouse Care comes to wherever the car is stuck, tests it on the spot and replaces the battery if needed to get it going straight away, start-stop coding included.
Is it risky to jump-start a modern car?
Connecting incorrectly can damage the electronics of recent vehicles. Follow the clamp order, or have a mechanic test it properly with a multimeter to avoid costly damage.