The average cost of repairing failures caused by electrical gremlins has increased by nearly a third (32%) over the past five years for cars that are more than three-years-old, according to Warranty Direct.

Its reliability index shows that the average cost of repairing failures caused by electrical faults is £300, but can rise as high as £2,804.

Electrical faults are the most common across all cars on Warranty Direct’s database of 50,000 policies, with almost a quarter (23%) needing a repair every year.

The number of electrical faults has increased by two thirds (66%) over the past five years.

While relays and alternators are the most likely components to break, newer electronic innovations like parking sensors are typically among the many faults reported.

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David Gerrans, managing director of Warranty Direct, said: “As automotive technology continues to advance, cars get more and more complex. Nowhere is that more so than in the field of computer technology and other electronics.

“While these advances can undoubtedly improve the performance and safety of cars, they also have a knock-on effect on how often they fail and how much it costs to repair them.

“Workshops now need advanced diagnostic tools to safely and effectively fix cars and, in some cases, it appears only franchised dealers can access some of the systems on newer cars, meaning that the customer is hit with a higher labour rate bill.”

Among the cars most likely to feature a failure are luxury and premium brands, like Porsche and Bentley, while Japanese brands Subaru, Mitsubishi and Daihatsu have the soundest electronics . Only one-in-seven Subaru models suffer gremlins.

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