For a family of mice in search of an ideal winter residence, the top of the cabin filter in a frequently driven car is prime real estate located in the "Goldilocks zone". Just the right temperature and size, and inaccessible by predators. For a mouse, who can pass through an opening as small as a USA 10 cent coin ("dime"), entry is easy. At the base of the windshield is a plastic panel the wiper shafts pass through, known as the windshield cowl panel. Below that panel is where the wiper motor is located. The size of those openings are considerably larger than the wiper shafts, and there are often gaps of sufficient size at each end of the panel. There are drain passages from the cowl to the pavement below as well. Located below the cowl panel is a fresh air opening, approximately 3 x 6 inches in size, that leads directly to the cabin filter.

There are 2 popular ways to block this entry route:
-1- Remove the cowl panel and fasten 1/4 x 1/4 inch (or smaller) metal screening over the fresh air opening.
-2- Develop the habitual routine of switching the HVAC intake air path to "recirculate" just before turning off the engine. This will move a flap in the climate control mechanism that blocks the intake air path between the cowl and cabin filter.

 

excellent tips
thank you.

 

I live out in the boonies where field mice, squirrels, chipmunks and white tails far outnumber our two legged species. Mice invasion was/is the main battle for me. I've had mice nest in engine air filter ( '16 Lexus Nx200T ), cabin filter and under intake manifold of V8 where they took out one of the two knock sensor wiring harness ( '05 T4R ), starter wiring harness ( '01 Honda ATV ). For my vehicles, the installation of a fine wire mesh ( 1/4" x 1/4" ) at the air intakes prior to filter worked best. Its been 5 years since without any more incidents. For my ATV, moth ***** inside a zip lock bag perforated w/a few small holes has work wonderfully. I've not come across a good way to keep mice out of the V8 valley ( a warm & great nesting place for mice ) of the T4R. To counter any potential attacks, I routinely/regularly blast the area with compressed air. Again, so far so good. To protect stuff inside my garage, mice traps with peanut butter set just inside both corners of garage door, had proven to be a sure killer.
@n0v8or great #2 tip. Tks.