Turkey's Competition Authority discussed earlier findings from a preliminary investigation and decided to open an investigation.
Turkey's Competition Authority opened an investigation against German automotive car manufacturers Volkswagen, Mercedes-Benz and BMW.
On June 11, the authority discussed findings from a preliminary investigation and decided to open an investigation according to a press release on Wednesday.
Brands being investigated under automative giant Volkswagen also include Audi and Porsche.
The investigation included claims on the maximum speed limits for the radar speed control system and roof hatches, the use of gasoline particulate filters, sensitive information on selective catalytic reduction (SCR) technology and AdBlue tanks.
Canceling plan for new Volkswagen plant in Turkey
Meanwhile, German automaker Volkswagen earlier said on Wednesday it is halting plans for a new factory in Turkey, saying that the steep drop in demand for cars worldwide caused by the coronavirus pandemic means the manufacturing capacity is no longer needed.
The 1.3 billion euro ($1.4 billion) plant in Manisa on Turkey's western coast was to make the Volkswagen brand Passat and the Superb, a sedan from its Skoda brand, starting in 2022 with an annual capacity of 300,000 units.
The plans had met with opposition from German labour unions and Volkswagen then faced more criticism after Turkey launched its anti-terror operation in Syria.
The project had been on hold since last year.
The company said that the pandemic had pushed market growth expectations far into the future and that “the construction of additional capacities is therefore from today's viewpoint not needed.”
The plant was originally intended to supply vehicles that would satisfy what was previously envisaged as growing demand in Eastern Europe and the Middle East. The company said it would carry out all its planned vehicle projects with its current factories.
German authorities search Continental, VW as part of diesel probe
Meanwhile, German prosecutors have extended their diesel emissions probe to include auto supplier Continental for its role in supplying engine components, searching the company's offices and those of automaker Volkswagen, the companies said on Wednesday.
Prosecutors in Hanover, Germany conducted the searches as part of an investigation into how a 1.6 litre diesel engine came to violate emissions rules by masking excessive pollution levels.
Premises in Hanover, Regensburg, Wolfsburg, Gifhorn, Berlin, Frankfurt und Nuernberg were searched by 76 Police and four prosecutors, a spokesman for the Hanover prosecutor's office said on Wednesday.
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"We are investigating employees of Continental for abetting fraud and for providing false documentation," Prosecutor Oliver Eisenhauer said, adding that seven engineers and two project leaders were among the accused. Two business heads and a compliance officer were also cooperating with the probe, he added.
Continental said in a statement that several of its offices had been searched, adding it was cooperating with the authorities, but declined to comment on the investigation.
A Volkswagen spokesman said the carmaker was cooperating with the probe in the capacity as a witness, given that VW has already settled with prosecutors in Braunschweig.
The Hanover prosecutor's office said the Hanover probe was an extension of the prior probes against Audi and VW.
The WirtschaftsWoche magazine had earlier reported that prosecutors in the northern German city of Hanover had searched offices of Continental and carmaker Volkswagen.