What Causes Water Leakage in the Front Passenger Side of a Mercedes-Benz S350?
2 Answers
Mercedes-Benz S350 front passenger side water leakage causes and solutions are as follows: Causes of water leakage in the front passenger side of a Mercedes-Benz S350: Water leakage under the front passenger seat is likely caused by door leakage. If the window regulator has been replaced, it may be due to improper sealing of the door waterproof membrane after the replacement. This happens because the waterproof membrane needs to be peeled off during the regulator replacement process. If the membrane is not properly resealed, heavy rain can cause water to enter the cabin. You can perform the sealing work yourself or replace the waterproof membrane. Solutions for water leakage in the front passenger side of a Mercedes-Benz S350: If you hear noticeable sloshing sounds when opening/closing doors or while driving, this indicates accumulated water inside the door panel. Simply use a thin wire or small screwdriver to unclog the drainage holes - this is something you can easily do yourself.
I've been repairing cars for many years, and water leakage in the front passenger side of the Mercedes-Benz S350 is a common issue. The most frequent cause is clogged sunroof drainage holes, where leaves or mud block the path, preventing rainwater from flowing into the chassis and instead seeping under the carpet. If the sealing rubber along the door edges becomes aged or deformed, water can seep in through the gaps. Another problem could be with the air conditioning drainage pipe—if it's misaligned or clogged, condensation water may leak into the front passenger area. Aging windshield seals are also a culprit, allowing water to infiltrate during heavy rain. I recommend first checking the sunroof drainage outlets and cleaning them with a thin wire or compressed air. If the carpet gets wet, dry it immediately to prevent electrical shorts. Avoid parking under trees regularly, and during routine maintenance, have a technician thoroughly inspect the sealing conditions. These issues aren't difficult to resolve; the key is addressing them promptly.
