Leaky Benz May Throw Codes
Mercedes-Benz notes that some 2018 C300 vehicles may experience a no-start, instrument cluster messages (do not shift, visit workshop; ESP inoperable; active lane assist inoperable, etc.), water entry into the passenger side footwell, or possible multiple CAN fault codes/messages.
This may be caused by missing body seam sealer under the battery tray or at the crossmember under the windshield.
Missing seam sealer can result in water intrusion on electrical connections. If missing, apply seam sealer P/N A 003 989 98 20.
Examples of missing sealer.
Example of applied seam sealer.