The root cause for the fire risk has been traced to a leakage in the coolant pump. Mercedes-Benz intends to replace the switchover valve that switches the flow of coolant from one pipeline to another. As part of the recall, the German automaker will also perform a software update on these vehicles.
Daimler AG expects to call back the first vehicles by the end of January 2022, but only time will tell if the Three-Pointed Star is able to source sufficient components by then. Oh, and by the way, Merc recommends driving these vehicles “particularly carefully” until they're fixed.
In alphabetical order, affected nameplates include the C-Class, CLS-Class, E-Class, G-Class, GLC-Class, GLE-Class, GLS-Class, and S-Class fitted with the OM 654 four-cylinder diesel or the OM 656 six-cylinder diesel.
The 654 was introduced in 2016 in plenty of nameplates, ranging from the A 200 d all the way to the GLE 350 de 4MATIC. The single-turbo diesel features aluminum for the block and head and a 15.5:1 compression ratio.
The 656, by comparison, is a straight-six diesel with a single-turbo setup and a stepped-bowl combustion process. Introduced in 2017 by the S 350 d and S 400 d, this mill uses steel pistons due to steel’s lower thermal conductivity that improves the powerplant’s thermodynamic efficiency.