The advertising watchdog has tackled Mercedes-Benz UK over its use of an advert claiming that fitting copy parts could result in legal liabilities after a crash.

It objected to a trade magazine ad which included text showing a nearside front wing and stating: "A Mercedes-Benz copy part may be used as evidence against you. Did you know that under current corporate legislation fitting a copy part that later fails to perform as required in a collision, could have significant consequences?

The ad continued: "Only Mercedes-Benz Genuine Parts have been specifically designed and tested to ensure that, in an accident, the vehicle impact absorbing zone and passenger protection area work as Mercedes-Benz intended. The evidence is irrefutable, always fit Mercedes-Benz Genuine Body Parts. Any other choice could be criminal".

Following a challenge by SEL-Imperial, a distributor of non-OE crash repair parts, The Advertising Standards Authority (ASA) ruled it was misleading and ordered Mercedes not to use it again.

The ASA found that there was no evidence from Mercedes which indicated Mercedes body panels, such as the wing pictured in the advert, had specific functions in a crash, or had been designed to perform in a collision.

"We did not see evidence that the car would perform differently in a collision with a copy part rather than a Mercedes genuine part fitted. In addition we did not see evidence that Mercedes genuine parts had undergone specific collision testing as stated in the ad," said its ruling.

The ASA acknowledged that some Mercedes genuine parts such as bumpers or bonnets had safety functions to perform in a collision, but noted that the ad referred to Mercedes genuine parts generally, and showed a nearside front wing as an example.