Flat Battery? What to Do Now

Battery warning light: what to do if it comes on while driving

A battery warning light on the dashboard can mean the charging system has stopped charging the battery. Possible causes include the alternator, the belt that drives it or the wiring. The battery itself may be fine. While the light is on, the car may be running on the charge left in the battery, so it can keep going for a while and then stop.

• Turn off electrics you don't need, such as the heater fan, heated screen and seats, and the radio.
• Head for a safe place to stop, such as a car park or a lay-by.
• Watch the other warning lights. On some cars the same belt drives other parts, so if a temperature warning comes on or the steering feels heavy, stop as soon as it's safe.
• Once you've stopped, the car may not restart. Plan for that before switching off somewhere awkward.

A charging fault needs a garage to look at it. If the car can't be driven there safely, tell us the warning light was on before it stopped, and request a recovery quote to your chosen garage.

Why car batteries go flat

• Lights or accessories left on, such as headlights, an interior light or a charger.
• Short journeys, which may not give the battery time to recharge after starting.
• A car left standing, because a battery slowly loses charge and some cars draw a little power while parked.
• Cold weather, when a battery gives less power and a weak one may struggle.
• An ageing battery, which holds less charge over time.
• A charging or electrical fault, which a garage can test for.

Checks before a jump start

A minute of checks keeps things safe, whoever does the jump start.

• Look for anything left on, and switch it off.
• Check the gear selector and pedals. An automatic may need to be in park, and a manual may need the clutch pressed. Your handbook shows what your car needs.
• Look at the battery without touching it, if you can see it. If it's cracked, swollen or leaking, don't try to jump start the car.
• Read the handbook before using jump leads or a booster pack. Some cars have set jump points, especially where the battery sits in the boot, and some handbooks say not to use the car to jump another car.
• Keep sparks and flames away from the battery.
• On an electric or hybrid car, the 12V battery can go flat and stop the car switching on. The handbook says whether and how it can be jump started. Don't touch high-voltage parts; on many cars their cables are orange.

If you'd rather not do it yourself, request a jump start quote. If the lights work normally but the engine won't turn over, the car won't start guide covers other possible causes.

If the battery keeps going flat

A jump start may get the car going, but starting doesn't prove the battery or the charging system is sound. If the battery goes flat again, possible reasons include:

• A battery that no longer holds its charge, so the car won't restart after it's parked.
• A charging fault, sometimes with the battery warning light on.
• Something drawing power while the car is parked, such as an electrical fault.

A garage can test the battery and the charging system to find out which. Battery testing and replacement may also be available from a mobile battery service at the car. Snap arranges a jump start, or recovery to your chosen garage if the car needs moving.

If the car won't start, or might stop on the way, request a recovery quote and tell us what happened after the last jump start. If the car is safely parked at home, the move can be planned: in the quote form, choose "On or by a specific date" and pick a day your garage can take it, or say you're flexible.

How your quote works

Tell us where the car is, what happens when you try to start it and whether the battery light was on. Snap assesses the job, checks prices and availability with suitable independent operators covering the area, and sends you one quote: the total for the job, with the booking fee and the operator's charge shown separately. Nothing is booked until you accept.

Your quote depends on the pickup and drop-off, the car's condition, access and operator availability. You see the total for your job before you accept. As indicative ranges, a jump start is typically £50 to £100 and a local tow up to 10 miles is typically £50 to £150, including the booking fee. See the jump start service, and the car recovery cost guide.

If the jump start doesn't get the car going, the operator may charge for the attempt, and a tow is quoted as a separate job. The quote is built on what you describe, so if the car or the access turns out different, the price may change.

What to tell us

• Where the car is and your reg. A postcode or what3words address, and the level and any height limit in a car park.
• What happens when you try to start it: clicking, a slow turn, nothing, or lights that come on and fade.
• Whether the battery warning light was on before the car stopped or wouldn't start.
• Whether it's been jump started already, and what happened afterwards.
• Whether it's an automatic, keyless, electric or hybrid car.
• Where it should go if it needs a garage.

Paying for the job

• Your quote shows Snap's booking fee and the operator's charge separately.
• Once you accept, you pay the booking fee to Snap by bank transfer, using the details on your tracking page. You get a receipt for your booking fee.
• You pay the operator's charge to the operator when the job is done.
• We don't take card payments on this website or ask for your card details.
• Cancel within 15 minutes of confirming, or before an operator is assigned (whichever comes first), and the booking fee is refunded in full. See how paying works, and cancelling and refunds.

Flat battery questions

Can you jump start a car if the battery is completely dead?

Sometimes. A jump start may restart a car with a discharged battery if the battery is undamaged, but a battery past recovering may not take a jump, and the fault may be something other than the battery. If the car still won't start, it may need recovery to a garage.

How long should I drive after a jump start?

It varies by car and by battery, so there is no single figure. A longer drive gives the battery more chance to recharge than a short hop. If the car won't start again afterwards, have the battery and charging system checked by a garage.

What does the red battery light on my dashboard mean?

It can mean the battery isn't being charged while the engine runs, for example because of the alternator, its belt or the wiring. The car may be running on the battery's remaining charge and could stop. Turn off electrics you don't need and stop somewhere safe.

Why does my battery keep going flat?

Possible reasons include a battery that no longer holds its charge, a charging fault, something drawing power while the car is parked, or a run of short journeys. A garage can test the battery and charging system to find out which.

Can a car with a flat battery be taken to my own garage?

Yes. Give the garage's name or postcode as the drop-off and check it can take the car. Your quote is for that journey.

Related help

• Car won't start, and the battery may not be the cause.
• Jump start, for a car with a discharged battery.
• Car recovery and towing to your chosen garage.
• What car recovery costs, and what changes a quote.
• Car breakdown help and recovery guides.