Nissan Altima water accumulation on back seat carpet behind passenger seat after AC plug unclogging on Nissan Altima

Some Nissan Altima owners report experiencing water accumulation on the back seat carpet behind the passenger seat after unclogging the AC drain. This issue may arise if the AC condensate drain line is not properly cleared, leading to moisture spreading to the rear footwell and under the carpet. Owners emphasize the importance of thoroughly drying affected areas to prevent further damage, as water accumulation can potentially harm electronic components under the driver's seat. The root causes of this problem can include clogged sunroof drains, windshield leaks, or blockages in the evaporator condensate drain tube. Additionally, moisture in the back passenger seat area may result from both external factors, such as leaking sunroofs and doors, and internal issues like AC evaporator malfunctions. To prevent future leaks and carpet damage, regular maintenance of the AC system, sunroof drains, and windshield seals is recommended. Ensuring the evaporator condensate drain tube is clear and functioning properly is crucial for avoiding water seepage into the back seat floor.