Smell from A/C

One quick way to get the odor out is to spray Lysol Fresh Linen scent into to intake grille below the passenger wiper (outside). Turn the fan on Hi and the mode to "outside air". Then spray in the grille generously. The scent will be a bit strong at first but will wear off in a day or so. If this doesn't work, check the cabin filter (behind lower glove box) for debris or perhaps a dead rodent. Be sure it was really changed out with your July visit. It's been noted rodents can get in that way on some G3s not stored in a garage.

If you really have mold in the evaporator coils, they need to be professionally cleaned...unless someone here knows how to gain access to the evaporator coils?

 

The humidity is usually low where I live and I never run the AC in recirculation mode. I always turn the AC off the last minute or so before I reach my destination, and have never had an AC odor problem with any vehicle I've owned.

 

When I was in for an oil change this week, my dealer has a sign posted with a picture showing the A/C with lots of mold and build up on it and the service person said that they recommend that all Toyota models with A/C get a service done 'about' every second visit (of the recommended service visits, ie. every 16km) which involves spraying with 2 cans of 'substance' (he was very vague about what exactly they were using, only that it would help with the problem). This seems unacceptable to me...I have had A/C in my cars for the past 20 years and have never had to do this type of expensive 'maintenance' to prevent smells and unhealthy conditions in my car (I am allergic to molds). Does anyone know if this is a problem with Toyota A/C's only or industry wide problem...I am going to call Toyota Canada and see where they stand on this issue...before I bought my car, I repeatedly asked about maintenance and was repeatedly assured that the maintenance was the exact same as my Corolla, and there was never any mention of this problem with the A/C or that I would require this expensive fix (he told me that the use of these sprays every second visit would cost me over $100 per time)

 

I see you live in Toronto so perhaps in the humid summers, mold buildup on the evaporator coils is a possibility. Even here in the southwest, we eventually get mold and scum buildup from dust on our evap coils. By their nature, they get moist from use (the water dripping out of the underside of the car in summertime is from these coils).

In most cars I've owned, you could access the evaporator chamber from the firewall and do the "spray" treatment yourself. Products like Coilclean from Ace Hardware would do the trick. Coilclean is only $14 and would do several cleanings - again, if we knew how to get access to the evap coil chamber in a Prius.

Get your dealer to tell you where the evap coil chamber is...as far as how often this should be done depends on the AC usage and mold issues in your area. Once a year should be plenty, IMO.

 

As the first poster pointed out - there are MANY instances of mice getting into the AC duct - it seems to be the preferred spot for them to hang out.

Pull out your cabin air filter and look inside...

I'd check into this quickly as they eat wires - and that's very very expensive. I park my car in the garage, but have bait traps all over the place.

Looking at those threads again tells me to make a bee line to the hardware store and get some chunks to store in the engine bay - as an added precaution....

 

UPDATE: I perused my online repair manual (page 6190) and found the location of the evaporator coil. It's in a horrible location - below and to the left of the blower motor assembly. For those of you who change your own cabin filter, it's set forward in the low-bridge console area. I can't see a way to access it easily to spray the coil with a cleaner to remove mold. No wonder the dealer wants $100 for the job.

 

I barely ever even use my A/C...in a year and a half I have only ever had it on a handful of times although I do realize it comes on when the front defroster is activated,...even then I try to turn it off as quickly as I can safely do so...is this not poor design to have a component of the car that is prone to molds in a highly inaccessible location?...if a children's toy had internal parts prone to mold there would be a recall and a fix to the obvious design flaw...this is afterall a safely issue here...regarding the health of the vehicles occupants...I think that all car manufacturers should be addressing this health issue...this is not a normal 'wear and tear' maintenance problem, this is sloppy design...there should be adequate ventilation for the coils or a fan to dry them off...no where else do we 'wait' for mold to accumulate then attempt to spray it off...we prevent that mold from accumulating in the first place...I have never had to address mold issues with my home air conditioner or the air conditioners in all my previous cars for the past 20 years...

 

By the way, thanks for going to the trouble of finding the location of the evaporator coils....just on my way out to duct tape mouse traps to my front bumbers and install a heat lamp over those coils to dry up the excess moisture....

 

Evaporator coil location

For those of you who have changed your cabin filters, here's where the AC evaporator coils are for a Prius:




In the first diagram, you'll notice the rectangular shape which is behind the glove box for the cabin filter. So you can see in the second diagram that the evaporator coil is buried behind the low-bridge console.

Most evap coils are accessible from the firewall so periodic "de-molding" is possible. I can't see a way to do it with a Prius.

 

Re: Evaporator coil location

Failure of evap coils is fairly common. Not sure about Toyotas but on many other cars. They start to rust and is a fairly common point of failure of the a/c system. Some cars it can be worse than you'd think to replace them - in a Volvo it's a solid 10-12 hour (billable) job for a tech to do it. They have to completely remove the entire dash down to the firewall. $1000+ job. Anything you can do to keep the a/c evap dry, like turning the a/c off and recirc off a few miles from home will help immensely in keeping your evap coil in good condition with low mold buildup.

I would be cautious about spraying just any type of spray on it, they are made of aluminum (IIRC) and you need to make sure the chemicals in the spray aren't going to pit it.

 

Re: Evaporator coil location

Good point about using the wrong product for cleaning the coils. There are many products available for mold removal that if used correctly are safe for use on aluminum. Usually these products are acid-free and only require them to be on the coils for 10 minutes or less before a good rinsing. That's what kills the mold and removes any dirt build up which then all comes out the discharge drain below the coils.

The problem with the Prius design is the difficult location to access the coils. My guess is that if the evaporator coil failed, both the sky-bridge and low-bridge consoles would need to be removed first just to get access to the evaporator section. As far as cleaning the coils, I can't see a way to do it but maybe there's a less invasive way. If a dealer can do it for $100, they must know this. Perhaps the blower assembly removes easily and the coils could be cleaned from that side. Just speculating.

 

So, let me get this straight. Car manufacturers KNOW of this problem with A/C's and yet they design the cars without trying to make it any easier to control the situation or make it easier to clean...what, they can throw crap loads of technology in a car but can't rig up a simple fan to make sure coils are dry, or at least make it accessible to inspect and/or clean...I find this very unacceptable...especially when it involves a safety and health issue...its like making seat belts that they know will rust and fail when used....Where is Ralph Nader when we need him?? And by the way, does he own a Prius?
And thanks for the diagram, much appreciated! I have now decided to train the mice that get in anyhow to make their way to the coils with soft clean mini rags and wipe them dry...wish me luck!

 

I am also having the same problem, I just discovered it last 2 days when I see mouse poops under my car and begun to worry that mice hid in my car.

 

I called Toyota Canada today and they were very sympathetic about my concerns regarding the dealer recommended regular treatment to the condensing coils, they said that they rely on toyota customers to contact them if they are having problems with mold etc in order to decide whether to "launch a campaign"...
Excellent customer service from Toyota Canada...I am going to be on the lookout for mice poop...and be very vigilent about any unusual smells...

 

seb33: Just an FYI so Toyota doesn't get the wrong coil in a campaign. "Condenser" coils are located behind the lower grille outside the car. They too can get dirty and less efficient but would have nothing to do with the air you breathe in the cabin. Condenser coils lose the heat from the refrigerant after it has passed thru the evaporator coils. The evaporator coils get cold from the refrigerant first compressed into a liquid and then passed thru an orifice converting it to a gas. This is the general process for refrigeration. The cabin air is then blown thru the evaporator coils to cool it and in the process, also removes humidity creating condensation. It's this moisture on the coils that can pick up airborne mold (and dirt) causing a buildup problem. That is what you smell when the coils have mold on them. I'm sure in humid areas, a dealership recommends cleaning the coils periodically. What we don't understand is how they do it.

On my SLS, there was an easy to reach access panel under the hood you could open and spray a coil cleaner onto the evaporator coils and then rinse. As simple as that and all mold and dirt was flushed out the drip release hole.

 

Thanks for the clarification, the service advisor was very vague when he showed me the posted sign with a picture of mold on a structure composed of a series of tubelike pieces...when I spoke to Toyota Canada about it I was mainly inquiring about the need for the regular spraying to prevent mold from developing, or cleaning of said mold...I will use the term 'evaporator coils' in the future...
I guess I got confused in terms because it is the condensation on the evaporator coils that causes the trouble