I like to keep a plastic box in the unused space below the passenger seat*. Is this vent related to battery (or other system) cooling? If it is simply an air vent for rear passengers, I will not be concerned with blocking it. * I keep my tire repair kit in it (small air compressor, tire plug kit, pliers). [I have a Plug In Prius w/o a spare tire and the OEM compressor w/ goo ruins the air pressure sensor.]
It's for main battery vent system. If you are talking the left rear passenger seat vent. From the manual Hybrid battery (traction battery) air vents There are air intake vents on the side of the rear right seatback and on the front corner of the left rear seat cushion for the purpose of cooling the hybrid battery (traction battery). If the vents become blocked, the hybrid battery (traction battery) may overheat, leading to a reduction in hybrid battery (traction battery) output.
Yes it faces rear. It is underneath the front of the front passenger seat. Duh (tks), it does blow air from the ventilation system and changes with the fan speed from the cabin temperature control. It is not related to the traction battery's cooling vents located at the lower left of the backseat bench and at the far right backseat seatback next to the right rear door.
How about a picture so we know what you're talking about? As you have described, it is probably the rear seat area HVAC register. Blocking it would diminish the amount of forced air into the rear seating area. Bear in mind that your traction battery air inlet is in the back seating area.
The grate between the right seat back and the right door... that's the traction battery cooling air intake... never block that one. The other vent under the seat is HVAC... block that one all you want... if need be. Shouldn't compromise anything.
That's the vent that will keep your tools warm or cold depending upon what temp you have the heat or AC set for Mike
I've not heard of a cooling vent at the lower left of the backseat bench and can't see it in my 2010. Can you describe it further or add a photo?
The "cool air inlet" is at the left side of the rear seat (if you're facing it) or upper right of the rear seat (driver's perspective). Photo credit to jayman.
I do not know were to get a photo of it. You can read a bit from my 2012 plug-in manual. see post #4. You will not have this in your 2010, I am not positive but I believe it was new in 2012 plug-in and may be only in plug-in it may be the only ones to have it, I'm not sure.
I am sorry for the confusion. Mine is a 2013 Plug In Prius. So this 'extra' vent (as mentioned above) is just for PIP's. On the PIP, besides the (as you are sitting in the back seat) right side vent we all are familiar with, the PIP also has a vent on the lower seat cushion on left side. If you were sitting behind the driver, it would behind your left calf/ lower leg. I assume this is an additional air intake due to the additional lithium (traction) battery located where regular Gen III Prius' have their spare tire (PIP's don't have a spare tire). Again, sorry for creating confusion. I posted in the regular Prius thread because in most ways the PIP is identical to the regular Gen III.
It came standard in Australian 2010 Prius. Cools or heats rear passenger feet. Of course ours is on the left.
I believe our mate is referring here to the AC/ heating vent under front passenger seat, which was the vent that was inquired about in the original post. Our mate's passenger seat seems to have come from the factory installed on the 'wrong side'. This vent refers to the 'extra' battery vent on the left side backseat bottom, near left door (only on the PIP).
pretty funny how a perfect description of the 'vent under the passenger seat facing the rear' can be misconstrued as the cooling vent(s) for the battery.
That was my fault! I just assumed that OP was talking about the extra vent on the rear seat left cushion in our plug-in's. The reason I assumed that is because the rear heat / Air cond.ducts have been under the front passenger seat for Many Years...... and the Plug-in's vent in the rear cushion was new with the plug-in. My Bad! Sorry for the confusion!