It happened very close to Mercedes' facility in Stuttgart.

One of the main reasons why all automakers are extensively testing prototypes out on public roads is to iron out all the kinks before commencing series production of customer cars. Doing so greatly reduces the risks of a break down in the middle of the road — as it was the case with this one. While the test driver was waiting at a junction, the camouflaged next-gen CLS malfunctioned and the Mercedes employee was not able to bring it back to life.

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After turning on the hazard lights to alert the others about the car being stationary, the test driver stepped out of the prototype to grab the cover from the trunk. As a side note, we finally have confirmation the all-new CLS will retain its sedan body style and won’t make the switch to a more practical hatchback rear like one of its main rivals, the Porsche Panamera, has had since day one.

2018 Mercedes CLS prototype breaks down
2018 Mercedes CLS prototype breaks down

The unfortunate incident happened most likely while the vehicle was returning to Mercedes’ testing facility located very close to that junction. While we don’t get to see how it all ended, it’s easy to imagine one of the test driver’s buddies from Mercedes arrived at the scene to lift the car and transport it back to HQ.

Heavily based on the latest E-Class from where it will inherit most of the interior, the third-generation CLS is expected to debut in the second half of the year. While the outgoing model received a wagon derivative, the new version will likely be sold exclusively as a sedan. Just like before, it will be positioned between the E-Class and the flagship S-Class. It’s unclear at this point whether there will be a new CLS63 considering Mercedes-AMG is prepping a four-door GT.

A debut at the Frankfurt Motor Show in September seems likely, though Mercedes might decide to wait until early December for the Los Angeles considering at IAA it will show the Project One and that would steal the CLS’ thunder.

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