Mercedes-Benz is recalling just under 20,000 examples of the CLS-Class Coupe and E-Class Sedan to inspect the anchoring systems for their 12-volt batteries. Located in the trunk, the batteries can come free in a collision, removing the power source for various safety systems. Mercedes says this problem impacts the 2019-2022 CLS450 Coupe and AMG E53, 2019-2021 AMG CLS53 Coupe, and 2021-2022 E450.
“Due to a deviation in the development process, the 12V battery mount(s) might not withstand certain mechanical loading in the event of a crash,” the company’s defect report said. “In the event of a crash, the 12V battery could move in the spare wheel well. Thus, a detachment of the electrical connections from the battery cannot be ruled out. In that event, various post-crash functions such as eCall, electric seat adjustment, hazard warning lights, and automatic door unlocking could be impaired or inoperative. This may increase the risk of injury for the vehicle occupants.”
While this does not impair any critical safety systems, Mercedes determined that the potential impact to its post-collision systems was concern enough to initiate a recall. The issue was discovered in internal crash testing, and Mercedes says that it has only documented one instance of battery mount failure, but could not rule out the possibility of it happening in the real world. The company has already re-engineered the components for production vehicles, so any example produced from August 2022 onward already has the improved part. Owner notices should be mailed by the end of November.