There's no mention of intake vent filters in the 2016 HV owner's manual, there's a graphic showing where the intake vents are on page 78 in section 1-2, there's one on each side of the 2nd row seat base.

 

Again, does anyone know how to access the battery air filter elements on a 2018 RAV4 Hybrid? I’m helping a friend, and I looked at the base of the rear seat. I can see the filters thru the intake vents, but I couldn’t see an obvious removable panel. Do I have to take the rear seat out?

 

I don't think the 2018 has any filter. The seat bottom just pops out if you want to look around under there. Grab it at the back and yank it up.

 

I can see a filter thru the inlet grid. To get the lower back seat up, do I pull up on the front edge? That’s the usual way unless there are bolts holding it.

 

Just like in my 2010 Prius, the seat bottom seems to be easy to remove. I’ve seen a video clip of this for a non-hybrid 2018 RAV4. Pull up on the front of the seat at the right and left ends (not at the very ends, but along the lower front of the seat). It may take a bit of effort & require both hands for each side. Then, pivot the seat up to free the back edge of the seat (there are two metal loops on the seat that catch two downward pins). Lift the seat out of the vehicle.

I may have to just try this & see if I can find the filters. I’ll make a video of it for YouTube. The filters are too recessed beneath the seat to enable vacuum cleaning.

 

Check this out:

https://static.nhtsa.gov/odi/tsbs/2017/MC-10131893-9999.pdf

 

Two days ago (Nov 24/20) the Car Care Nut on YouTube has a video on filter access and cleaning titled - 2016-2018 Toyota RAV4 Hybrid Battery Fan Filters Maintenance,
located at -

Toyota did not do us any favors if this is the recommended cleaning method. As an aside, I feel that a routine vacuuming of the filter screen should be sufficient unless debris are noticed on the inside of the screen or on the foam filter under the seat.

 

Two days ago (Nov 24/20) the Car Care Nut on YouTube has a video on filter access and cleaning titled - 2016-2018 Toyota RAV4 Hybrid Battery Fan Filters Maintenance,
located at -

Toyota did not do us any favors if this is the recommended cleaning method. As an aside, I feel that a routine vacuuming of the filter screen should be sufficient unless debris are noticed on the inside of the screen or on the foam filter under the seat.

I followed this video on my 2018 RAV4 Hy, it only took me 15 min to do both sides, it’s not hard and goes back together easily.

 

Vacuuming is definitely enough. All the dirt is collected on the exterior of the filter and gets easily dislodged with reverse airflow. You may end up and a negligible fraction of blocked "squares" but even those can be opened up with the soft brush attachment.