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Top 10 most common breakdown causes

The RAC is launching a new service to predict the causes of breakdowns before they actually happen. The recovery specialist is developing a system that merges telematics (airline-style black box technology that monitors vehicles) with its historical breakdown data to let drivers know about likely problems before they’re stranded at the roadside.

Before the introduction of the new service, HonestJohn.co.uk mined the vaults of the RAC’s database to discover the 10 most common causes of a roadside breakdown and the average mileage at which they’re likely to occur.  

The 10 most common MoT failure points | Need a mechanic? Check out the Good Garage Guide

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A flat battery is the chief reason to prompt a call to a breakdown provider according to the RAC. The organisation says it fits around 100,000 batteries a year and typically attends over four times as many battery-related breakdowns annually.

It sounds simple, but you can avoid becoming one of the many by turning off or unplugging anything that might drain the battery when you’re not using the car. That includes the stereo and the likes of mobile phone chargers or cables.

Average mileage of fault: 45,957  


technispark    on 4 July 2016

Cars are really just too complex today to be reliable. We need to return to a concept where a car is first and foremost a means of getting from a to b rather than a computor on wheels, then we might have a reliable vehicle.

Dodgey    on 4 July 2016

I don't disagree in principle with the comment above, but you are effectively saying you prefer a car with a set of points, and a carburetter, no anti lock brakes, speedo's that can be rewound easily with a drill to falsify mileage, a distributor cap to attract rain and stop it in it's tracks if any moisture is within 5 miles and headlights that make it darker. Yes it would be more repairable but it would also break down a lot more too!

diddy11cg    on 4 July 2016

I have a 55 Reg 1600 Focus Zetec. I had an intermittent ignition fault that caused misfiring on two occasions with an engine warning light. It turned out to be rusty plugs and plug leads. My mechanic said it was caused by a leaky core plug that let water into the plug tray. I disagreed with him because the car has never used any coolant, in fact I have never topped it up and you would expect the coolant level to fall. The RAC man said it was a leaking bonnet so I beefed up the rubber seal but it happened again. I then read on Honest John I think, that the early Focus developed leaky screen washer jets and by placing some material over the plug tray in wet weather sure enough that was it. I then found that Ford had modified the jet assembly with a better quality rubber grommet . I replaced them and this solved the problem. It wouldn't happen on a modern Focus because the bonnet has a felt sheet attached to it and the engine has a plastic cover over it. My 55 Reg has neither.

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