Why isn't my stop-start working?

My stop-start engine stopped, as per normal, at a set of traffic lights - but then wouldn't automatically start again. Why's that?

Asked on 19 May 2020 by Paul Widnall

Answered by Dan Powell
Probably a flat or faulty battery. If the car been left standing for long periods without charging, it has probably lost its charge. A 30/40 minute motorway run at 70mph should remedy the problem. However, if the battery is over five years old, it might be better to replace it. Most batteries need replacing every five years.
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