A mold or mildew smell in your 2020 Lexus RX indicates moisture has been trapped in the cabin, likely from an undetected water leak. Beyond being unpleasant, mold can cause health issues and indicates potential damage to carpeting, insulation, and electrical components.
Where Water Hides
Common leak sources include clogged sunroof drains, door membrane failures, windshield seal deterioration, A/C condensation drain clogs, or door glass channel wear. Water pools under carpets where foam insulation traps moisture, creating perfect mold growth conditions.
Finding the Moisture Source
Feel under floor mats and carpets for dampness - the floor insulation can hold surprising amounts of water. Check trunk carpet and spare tire well. Inspect door panel bottoms and under seats. Use a moisture meter if available. The smell is strongest near the moisture source.
Mold Health Concerns
Automotive mold exposure can trigger allergies, respiratory issues, and headaches. The enclosed cabin concentrates mold spores when the HVAC runs. People with sensitivities may have immediate reactions. Even those without sensitivities can develop problems with prolonged exposure.
Remediation Process
Identify and fix the leak source first - drying without fixing the leak is pointless. Remove and dry or replace water-damaged carpet and insulation. Treat affected areas with antimicrobial products. Replace HVAC cabin filter. Run the HVAC on fresh air to help dry the system. Professional remediation may be needed for severe cases.