Mercedes-Benz says owners of its nearly 300,000 SUVs should park until further notice due to a potential problem that could result in a loss of braking power. NHTSA 2006-2012 issued a “Do Not Drive” notice for ML-Class, GL-Class and R-class vehicles until their brake boosters can be inspected.
According to Mercedes, these SUVs are shipped with brake boosters that can be worn out after prolonged exposure to moisture. If corrosion occurs, the structure of the internal components of the brake booster may crack, allowing air to enter the baking system and reducing braking efficiency. If enough physical pressure is applied to the booster hardware, it may experience a catastrophic failure that will lead to complete loss of braking power.
“In rare cases of severe damage, it is possible that a strong or stiff braking application may cause mechanical damage to the brake booster, resulting in a failure of the connection between the brake pedal and the brake system,” Mercedes said in a statement. “In such a very rare case, it will not be possible to reduce the speed of the vehicle through the brake pedal. Thus, the risk of accident or injury will increase. The effectiveness of the foot-activated parking brake is not affected by this problem.”
Mercedes says the initial signs of failure include a soft brake pedal or audible signs of air in the braking system (the sound of pedals sucking, hissing or shortness of breath is a possible indicator of contaminated brake fluid). Mercedes says drivers should park these cars unless they are inspected by an authorized dealership.
“An authorized Mercedes-Benz dealer will remove the rubber sleeve and inspect the damaged vehicle’s brake booster housing,” Mercedes said. “Vehicles that do not show improved corrosion may be driven without any further action. Vehicles that show improved corrosion will be subjected to an additional test to ensure the effectiveness of the brake booster. “
“Vehicles that do not pass the additional test will require a brake booster replacement. The stop-drive notice will remain in effect for this vehicle until the brake booster is replaced. A repair is required at the event and cannot be done immediately, with an authorized Mercedes-Benz dealer with alternative mobility.” Will help to adjust a separate solution for the customer. “
Mercedes has been sending notices to owners since May 12.