Millions of motorists could be driving a car with a battery on the brink of sudden failure, new analysis suggests.
The findings come from analysis of more than 550,000 UK vehicles by automotive diagnostics app Carly. It discovered around 25 percent of cars may have a weak battery.
With a total of around 34.5 million licensed vehicles, this equates to 8.6 million British motorists at risk of a non-start failure due to a dead 12-volt battery.
Separate Carly data confirms this risk, with 12-volt batteries being one of the leading causes of a roadside breakdown.
Unlike major mechanical failures, battery decline is a slow-burn. “It’s easy for drivers to miss the warning signs until the vehicle suddenly fails to start,” said Carly’s Emma Brown.
“In modern cars, a weak 12-volt battery can affect far more than just starting the engine, which is why early diagnostics and better visibility of battery health are so important.”
Early detection can save money
Replacing a 12-volt battery typically costs between £150 and £330, according to Carly’s repair and maintenance cost estimator. This price includes fitting.
However, if degradation is left untreated, costs can rise further. A starter motor repair, for example, typically costs around £330, while alternator repairs can cost up to £800.
Subtle early warnings signs that a 12-volt battery is on its way out include sluggish or hesitant engine starts, headlights that briefly dim when the ignition is turned on, and stop-start systems that disable themselves without a clear fault message.
Some cars may show intermittent warning lights, particularly after being left standing for a while. Power steering that briefly feels heavy after starting the engine is another indicator of looming battery failure.
Ignore these warning signs and the risk of a sudden and disruptive failure increases significantly.
Carly’s solution? Its OBD2 scanner and app diagnostics, which plug into a car’s OBD port. The technology allows drivers to assess battery condition, read any fault codes and even view likely repair costs before visiting a garage.
Best of all, it’s affordable, with prices from £40. Much more palatable than the financial hit of an unexpected breakdown…
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