/ Motoring

Can breakdown services cope with modern cars?

Man pushing car

Although car reliability is better than ever, when modern motors do break down, their electrical complexity seems to be stumping breakdown services. So, can your car be fixed by the side of the road?

We tested a couple of electric cars recently and both of them broke down. This came as a shock (if you’ll pardon the pun) to all of us at Which? Car. It seems we’re just not used to cars breaking down any more.

It wasn’t always this way. When Which? conducted its first car tests 49 years ago, four out of the eight cars tested broke down within a year – some repeatedly. In fact, our Austin Mini was so unreliable that we sent it back and asked for another.

Compare that to our latest Which? Car Survey – just 15% of survey respondents called out a breakdown service last year – and that covers cars of all ages. Had we undertaken the same study in 1962, that figure undoubtedly would have been closer to 100%.

Breakdown services flummoxed

This vast improvement in car reliability is a good thing. Despite what a spanner-wielding member of the MG owners’ club might tell you, the possibility of a blown head gasket or seized piston does not turn a journey into an “adventure”. It just makes it more stressful and potentially wastes a lot of time. And I speak as somebody who’s owned plenty of temperamental old cars.

However, there is a downside to clockwork reliability. Of the 7,366 cars in our survey that left their owners stranded, less than two-thirds (61%) could be repaired at the roadside by a breakdown mechanic. Apparently a can of WD40 and a swift blow with a mallet will no longer suffice – modern cars are just too complicated.

Electronics are largely responsible for making cars more dependable and safer, so nobody is advocating a return to carburettors or binning anti-lock brakes. But much of the tech on modern cars is just window-dressing that adds complexity and weight. I don’t need to select from four suspension settings or switch between eco and sport modes – just set the car up properly in the first place.

Too complicated to repair?

Electrical systems account for by far the largest number of faults in the Which? Car Survey, yet it’s perfectly possible to build simple, reliable cars that don’t need expensive diagnostic equipment to be repaired.

My colleague Rob Hull has already bemoaned the fact that modern cars are so complicated that maintaining them is basically out of our reach – but this also affects breakdown services.

If this sounds like a rant about electrics (and, by extension, electric cars) it isn’t. I just think that sometimes technology can cause as many problems as it solves. And if cars can’t be fixed at the roadside, it makes breakdowns a major inconvenience when they do occur. So are breakdown services fit for purpose in a world of cars full of complex electrics?


Some valid points.
I too think more reliable but more technologically simple cars would make for an easier life.
However modern cars sell on gizmos and gimicks. These go wrong and yes fixing them at the roadside is not easy.
But give the breakdown services their due they still fix plenty of the common reasons for stoppage like batteries, radiators, drive belts, hoses and even sometimes alternators.
If the dash glows with electrical fault lights it’s serious, not necessarily because the problem is significant but often because without diagnostic kit you’ll be hard pressed find the offending sensor, probe or whatever.
It would not be practical to carry full diagnostic equipment around in an AA van to cover the many types of electrically complex cars commonly on our roads. But again breakdown services do often have “fault code” identification equipment. These are greatly simplified versions of the main dealer kit which will at least give them a clue as to whats wrong.

I think the comment “are breakdown services fit for purpose in a world of cars full of complex electrics?” is really the wrong way around.
It should be “are modern car electrics too complex for what is practical for breakdown services to fix at the roadside?”

Of course the answer is we all start demanding more simple cars, “some chance of that”.


Gone are the days of men in oily overalls with Birmingham screwdriver and adjustable spanner beating your car into submission! These days it is spotless white overalls, rubber gloves and a laptop.

The problems come when said laptop interrogates the management computer (ECU) which doesn’t divulge any error code. Then you really are in the ****.

It happened to me with a new VAG 1.8td PDI car. The intermittent fault was dead simple to a properly trained mechanic. The main relay (R109) that feeds 12v to the ECU and is activated when you switch on the ignition was occasionally not closing. Because there was no power to the ECU, the fuel injectors and pump won’t work. So despite all the dash lights running correctly and the starter motor turning over, nothing happened. And the ECU reports nothing because it isn’t powered on. When it first stranded us in an M1 service area, the Response vehicle plugged in their laptop but were unable to ‘talk’ to the ECU. Surely that was a strong clue as to the problem!

The garage didn’t have a savvy mechanic and they had the car for THREE MONTHS. In the end, I found an Internet forum that specialised in the VAG pdi vehicles and the genuine expert said that it sounded like R109 was faulty.

I emailed this information to the garage and they had no idea what I was talking about. After another month – during which time the garage changed the ECU and several other components at huge expense to themselves – I called VAG Europe HQ and reported the problem to them.

Three days after calling VAG, my car was returned! Compensation: I got three years’ free servicing and at least I had an upgrade loan car for the duration.

But it shows that a simple fault that isn’t reported with an error code on the ECU has most of the garages floundering into unknown territory.

pickle says:
4 August 2011

Yes, cars are complicated these days but it not the complicated bits that cause most breakdowns. Chris said it all…The advantages outweight the snags in my view. My car is a diesel, 95g emissions, tax free and is suppose to give 74 mpg. Compare that with a prewar car unknown emissions, but quite a lot, 30mpg and fairly expensive tax for the time.
Mind, when the complicated bits do breakdown it’s usually a tow to garage job and often costly.
I look back with nostalgia to my 1932 Morris Minor – forever having to deal with the grease gun and adjust distributor points, but it never let me down – ever!


Last week I mislaid 2 sets of keys & totally dependent on car/van that holds mobility scooter .I have no carer of assistance at home. Not one person could assist as had urgent things to do last weekend . Noone could do a duplicate key quoting 5-10 days to do then taking vehicle in van on a trailer . This could have cost well over £300 even though had key loss on insurance which didn’t kick in for 3 days. In the end my sister & brother in law drove over 10 miles to search & lend my mothers kangoo. After an hour my brother in law found them in the dustbin?? The duplicate set still have not turned up . As for the loan of a mobility Scooter for a week . This didn’t happen as Camden Council using people who haven’t capacity assess to discriminate with Managers complying and over 30 scooters not used.If you drive through central London regularly & member of numerous Shopmobilities including their own what is their & Islington’s problem? Why did they never address this issue when applied over 10 years ago?


Earlier this year an intermittent computer fault on my Mazda 3 became permanent and the local Mazda dealer fitted a new computer for around £1200. However what I found most worrying was that that price was conditional on my old computer being sent to Mazda for ‘reconditioning’, leading one to suspect that a simple repair made it good as new. Thus Mazda could well have made a good profit because one of their parts developed a fault – even they agreed it had nothing to do with wear and tear. Of course I have no idea what happened, but even if the old computer had to be scrapped it’s hard to see how something that looks like a car radio can cost well over £1000.

Charles says:
5 August 2011

My 23 year old Volvo 340 – (had it from new) never goes wrong.

It hurtles from London to Cornwall and the Lakes with an occasional shudder but all OK. Finally last week a fuel pipe perrished and the AA man replaced it in 3/4 of an hour with no charge.
When a tyre goes flat the AA change it and when a friend left the lights on for 2 days they sorted out the battery.

So yes lets go for some of the simple reliability and make cars less expensive. I would like a new one but the prices are silly!


Cars got a lot more reliable during the 90s; I suspect this was mostly because of the introduction of contactless ignition. But have they got any more reliable since about 2002? Not in my experience. What do the reliability surveys show?

(by the way, Charles has been very lucky…the Volvo 340 came out badly in Which reliability surveys, and mine was constantly breaking down…)


Replacement of carburettors with fuel injection systems was another great step forward, improving reliability and making cars much easier to start.