Mercedes-Benz (DDAIF) is recalling nearly 324,000 vehicles due to a water intrusion problem that could cause the engines to stall while driving, federal safety officials said.
The recall may cover 323,963 vehicles in the model years 2012 to 2020, according to a filing with the National Highway Safety Administration.
The affected vehicles include the ML550, ML350, AMG ML63, ML250, ML400, GLE450, GLE300, GLE350, GLE550, GLE400, AMG GLE43, and AMG GLE63. Roughly 1% of the vehicles are believed to have the defect.
Mercedes said that it is not aware of any crashes or injuries caused by the defect. The production of the affected units ended on November 25, 2019.
Water could infiltrate the rear of the vehicle and accumulate in the spare wheel well, which could intermittently contact the fuel pump unit.
Crash Risk Could Increase
"Consequently, the fuel supplied to the engine could be interrupted, which would lead to a loss of propulsion without warning. In such circumstances the risk of a crash could be increased," the filing said.
Drivers may be aware of water infiltration due to a damp carpet in the rear of the vehicle or the sound of water sloshing in the spare tire well.
In some cases, drivers could also be alerted to the condition by illumination of the check engine light in the instrument cluster.
Mercedes said it had been investigating the issue since 2018. Initial analysis identified no indications of a systemic failure that could account for water penetration into the rear of the vehicles or failure of equipment such as the fuel pump control unit, the filing said.
"Whether and how water might penetrate into the spare wheel well and whether such water ingress might affect the operation of other vehicle equipment are difficult and complex questions involving many variables and unknown factors," the filing said.
As a precaution, authorized Mercedes-Benz dealers will install a water drain plug in the spare wheel well on the affected vehicles, check for water infiltration into the spare wheel well, and replace the fuel pump control unit if necessary.
Earlier Recall Over Sunroof Problem
Dealers were notified of the recall on January 3. Owners will be notified of the recall before February 21.
Mercedes-Benz USA, the German automaker's U.S. distributor for passenger cars, recently recalled about 123,696 vehicles due to problems with sunroofs.
Mercedes determined that the bonding between the glass sunroof panel and the sliding roof frame might not meet specifications in certain models from the years 2001 to 2011 C-Class, CLK, E-Class, and CLS vehicles.
The adhesion of the bond might deteriorate gradually over time, an NTHSA filing said, and the specified durability requirements of the bond would not be guaranteed. As a result, separation of the glass panel from the vehicle "cannot be ruled out."
"This could increase the risk of a potential accident and/or injury for other road users," the filing said.
Separately, Mercedes-Benz said on Jan. 5 that it would install a network of 2,500 high-powered chargers in the United States by 2027. The country also plans to install Mercedes-brand chargers in Europe and China.
