— A Mercedes-Benz C-Class recall has been issued for about 28,400 model year 2018-2019 C300, C300 4Matic and C43 AMG 4Matic vehicles to repair problems with the batteries.
Mercedes says the mounting bracket for the 12-volt battery may not be secured, allowing the battery to shift in a crash. This can disconnect the battery terminals and cause problems with activating the hazard lights or calling emergency services.
Additionally, busted mounting brackets can send a battery flying out of the engine compartment.
Mercedes was contacted by the bracket supplier in January about possible problems during the production of the mounting brackets. An investigation determined the tightening torque of the bolt connection between the battery mounting bracket and base plate was too high, causing cracks in the mounting brackets.
The automaker analyzed the effects of cracks and how long it takes for the batteries to loosen. Engineers found road vibrations increased the size of the cracks to the point the mounting brakes broke.
Drivers may notice rattling or knocking noises if the batteries are loose in the engine compartments.
About 26,600 of the recalled vehicles are in the U.S. and another 1,800 are in Canada.
The recall is expected to begin October 8, 2019, when dealerships will replace the battery mounting brackets.
Affected C-Class owners with questions should call 800-367-6372.