2006 Toyota Avalon Owners Manual - Page 235

'06 AVALON_U (L/O 0508) 4. Pull the filter out of the filter outlet. Inspect the filter on the surface. If it is dirty, it should be replaced. When inserting the filter in the filter outlet, keep the arrow pointing up. INFORMATION The air filter should be installed properly in position. The use of air conditioning with the air filter removed may cause deteriorated dustproof performance and then affect air conditioning performance. 235