V8_Fan

Does any know at what frequencies does one change the front/rear seat A/C filters and rear optical purifier filter? The owner's manual justs lists 10K mi intervals for the A/C filter (I take that to be the cabin air filter behind the glove box?). Beside the cabin air filter, how many other filters are there and where are they located?

DNC

Jim, Don't forget you have a small air filter in the trim around both back door jams. These are very easy to change and I would change them each time you change your cabin air filters.
I think you will discover your car's seat air filters will last a good while. I change my car's seat filters once a year and according to the way they look it appears to be overkill but the seats have such little air flow I want to make sure I keep them changed.

CG lover

we run our front car seats air flow most all the time and even after a year the filters still look clean,, I have changed them once in our four years of ownership,, the glove box filter I will check every oil change as it can gather large debris items and at least shake them off if there,, I have found that filter can easly run 15K or more miles,, guess it depends on where your driving also,, I know the dealers are quick to recommend a change on that main air when they make $85 for a five minute job,,

if you have the trunk filter which I have, mine has never been changed,, the rear air unit is seldom run (only whe the grandkids are back there messing with everything) and in the 46K miles on the car I doubt it has four hours of use moving air over that filter,,

Derry

jayclapp

In Phoenix you'll probably want to leave the rear A/C on all the time. I change both cabin air filters every 10,000 miles. Easy to do yourself.

The tiny rear door sill filters easily pop out. They are washable, and I just clean and reinstall. They look new after a good cleaning and I don't see a reason to replace them. They are very coarse and I doubt that they do much.

V8_Fan

Thanks. Are there any filters under the rear seats or are the ones in the door sills THE rear seat filters? I would think that the bulk of the filtration is done by the cabin filters. Here in AZ, the air is dry and dusty, so my A/C tends to be on recirc all the time (no risk of mold in the evaporator due to low humidity).

As I live in Tucson, AZ (still 104F today), the rear A/C will likely be on all the time as it is in my LX. When you mean "both" cabin AC filters, do you mean there are two behind the glove box, or do you mean one behind the glove box and one in the trunk. I was under the impression from the owner's manual that the one in the trunk is a special filter since it's for the rear deordorizer/purifier.

--Jim

jayclapp

By both filters I was referring to the filter behind the glove box and the one in the trunk. The filter in the trunk is special in that it includes a UV light to sanitize the filter. I think the tiny sill filters are for the rear seats, but I don't really understand how they fit into the system.

BNR34

iTrader: (1)

There is one filter under each rear seat, just like the ones under the front seats.

V8_Fan

Are the rear seat A/C filters the same part number as the front seat filters?

BNR34

iTrader: (1)

No, the ones in the rear are smaller.

I have the part # at home, I'll post it up if I remember.

V8_Fan

So to my understanding, the rear AC/seat AC need FIVE filters: the optical purifier in the trunk, one small filter under each rear seat, and one for each rear side door sill? Do you also have the P/N for the door sill filters? I tried getting them from Sewell, but the guy had no clue what I was referring to.

BNR34

iTrader: (1)

Well the optical purifier filter is for the rear AC unit, it has nothing to do with the rear AC seats.

Yes I have the door sill filter part # too. One tip for you, all the part # are on the filter itself, so if you pull them out, you'll see it. But I'll post them up once I get home. Honestly though, these filter don't get dirty much as they don't see much air flow, doing it is just to make yourself happy that you got new filters and they don't cost much, so it is a cheap happiness. I know how you feel though, I changed all of my filters when I 1st got my car, it felt good!

V8_Fan

I already changed the engine air filter...was pretty dirty after 20K (must have been the original, book recommends it at 30K mi). Although I bought a new AC cabin filter, the old one looked okay; had a bunch of leaves on it, but I shook those out. The owners manual says the dash display will tell you when the cabin filter needs changing, so I figured I'd do it then or at 30K mi, whichever comes first. The cabin filter looks to be of decent quality (charcoal?)

jayclapp

My 04 manual and schedule chart shows the cabin filter to be replaced at every 10,000 miles. If the maintenance is reset after installing the cabin filter it should warn when 10,000 is accumulated. If it's not reset, it won't warn again.

V8_Fan

That's what I figured. The light should come on at 10K miles like the engine maintenance light turns on at 5K mi. Maybe the AC light just comes on when the filter is dirty rather than at 10K mi? Either way, it sounds like it doesn't need changing yet.

jayclapp

You guys got my interest in the A/C system and revealed the filters beneath the front seats. I took one out and it was very dirty. I bought my 04 UL two years ago at 21,000 miles and now have 53,000 miles. I don't think these front seat filters have ever been changed. I can't even find anything in the manuals about them.

I tried blowing out the filter I took out, but that didn't work very well even though I thought the airflow increased a bit in comparison to the passenger seat. So I ordered new filters from my dealer for the front seats.

I think the front seat filters are in an extremely dirty environment. They point downward and are close to the front of the seat. Every time you get in the car you must stir up some dust from the carpet, etc., and this is the air supply source for the seat filter.

My dealer couldn't find any filters under the rear seat, only the sill filters. I can see where the rear seat air supply would be much cleaner than the front seats. Much less chance of dust being in the air at the sills as compared to being close to dirty floor mats. The air comes in from the door sills and have a rather large volume under the seat, which would let some of the dust in the air settle out before getting to the cooler inlet for the seats.

Therefore, I could see why there might not be a need for filters under the rear seats, and if there are filters there why they might have a rather long life before needing to be changed.

Can anyone actually confirm that there are filters under the rear seat and what you have to do to get to them? If so, I would expect that they would be the same P/N as the front seat filters (P/N 88921-50010).

Thanks.