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Car won't start: is it the battery?
Updated October 2026
Flat batteries are the most common reason for a breakdown call-out, especially on the first cold mornings of winter.
Signs your battery is failing
- Slow, laboured cranking
- Clicking but no crank
- Dim lights when starting
- A battery warning light
- The battery is more than 4 to 6 years old
Flat or faulty?
A battery that's simply flat (lights left on, short trips) can recover after a jump start and a long drive. If it keeps going flat, the battery or the charging system (alternator) may be at fault. Many parts stores will test your battery for free.
Jump starting safely
- Red lead: flat battery positive, then donor positive
- Black lead: donor negative, then an unpainted metal point on the dead car's engine
- Start the donor car, wait a few minutes, then start yours
- Remove leads in reverse order
Parts you'll need
Order online for delivery, or click and collect from a local GSF branch, often within the hour.
Some links on this page are affiliate links to GSF Car Parts: if you buy through them, we may earn a commission at no extra cost to you. It never changes our advice.
Modern cars with stop-start need specific battery types (AGM or EFB) and some need the new battery registering with diagnostic equipment. A mechanic can do this for you.
Need help?
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