Marketers of cars and other vehicles often want to highlight how fuel efficient the model in question is, so we thought it was a good time to offer some tips and advice about how to make sure these comply with the CAP Code.

Legislation requires that CO2 and mpg claims are displayed in vehicle advertising in certain media - CAP and the ASA can’t comment on the figures themselves, but efficiency claims are subject to the Code and the ASA does take action when these are deemed misleading.

What do I need to do if I’m making claims about how efficient a car is in my ad?

Regardless of how a car is powered, all MPG figures should be qualified where and whenever they appear in advertising. CAP advises that a disclaimer along the lines of “MPG figures are obtained from laboratory testing and intended for comparisons between vehicles and may not reflect real driving results” should be included wherever a fuel consumption figure is quoted.

What about electric vehicles and hybrids?

Gone are the days where all cars on the road were propelled by burning petrol or diesel, and the rapidly growing selection of vehicles powered by hybrid, plug-in hybrid, pure electric and now even hydrogen powertrains means marketers have to take extra care to ensure the claims they make about cars’ efficiency are not going to mislead consumers. Section 11 of the CAP Code (and section 9 of the BCAP Code) is concerned with environmental claims. The ASA Council ruled, in this case, that an MPG claim was misleading because it did not make clear that the figure, for a plug-in hybrid vehicle, was obtained after charging the car from mains electricity.

Particular care should be taken when advertising electric vehicles (EVs) or those which use a hybrid powertrain with electricity and petrol/diesel (HEV, PHEV etc). In addition to these qualifications, the ASA considers that efficiency claims for plug-in hybrid (PHEV) vehicles should be qualified to explain that the advertised MPG figure is achieved through a combination of petrol and electricity from an external source (more information can be found in the AdviceOnline entry Motoring: Electric Vehicles).

It’s important not to exaggerate the efficiency of a car, or its impact on the environment (see this article about environmental claims).

As always, the CAP Copy Advice team is on hand to help out if you have any questions.

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