There is another brief post on this subject. The issue is a stale odor coming from the HVAC vents. With my SC430 now 16 years old, I decided to try and clear this problem.

I believe that the dealerships offer a similar service but not sure what the price is. The whole cleaning process takes over an hour so I'm guessing they charge around $200 or so. I purchased the official Toyota product for a total of $30, delivered to my door.
Here is a photo of the item. It looks like they have a newer product available now as this part shows discontinued.



It is a two step process and the cans are marked 1 and 2 with decent but generic instructions on each. Begin by removing the HVAC filter located behind the glove box. There are other posts that describe this process. I'm ashamed to say my filter was looking pretty bad but the plan was to replace it any way.



Remove the filter from the carrier and reinstall the empty carrier and access cover panel. The next part is locating the AC drain hose under the car. This is the hose that can become clogged and cause wet carpets on the passenger side floor. While you can use jack stands to raise the car, I have access to a lift. If you use stands, aside from the usual safety cautions ensure the car is level so the AC drain will work as designed. Below are two photos of the AC drain hose looking up from below. The hose on my U.S. market L.H.D. SC430 is on the passenger side firewall near the passenger side front catalytic converter.





Insert the kit supplied tapered hose connector into the drain hose as pictured below. Wear gloves if the catalytic converter is still hot...



Dispense half of Can 1 into the hose as per the directions. Have a small drain pan handy. Remove the Can 1 hose from the AC drain hose. It takes a few minutes but the cleaning foam will change to a liquid and drain out the hose. The instructions say wait ten minutes but I allowed almost 20 minutes to drain all the cleaner before continuing with the 2nd half of Can 1. Repeat this process, using the rest of Can 1. After the cleaning liquid drains out, you are ready to continue.

Next the instructions say to disable the AC compressor. The easiest way to do this and allow the rest of the HVAC system to operate is to disconnect the AC compressor magnetic clutch power harness at the compressor. Pictures below.



Just depress the clip and pull to separate the two halves.



The instructions on Can 2 say to find an air intake under the passenger side dash. I couldn't locate a intake so I removed the AC filter cover and empty filter carrier assembly and followed the instructions while spraying Can 2 directly into the filter opening while running the fan on High and switching between Panel, Floor and Defrost setting every 45 seconds. The can is pretty much empty after the 45 second Defrost spray. When the can is empty allow the fan to continue another 5 minutes to dry the vents.

Next turn off the car, install a new AC filter in the carrier, reinstall the carrier and cover & reconnect the AC compressor harness. That's it.
I let the car sit overnight. This morning when I started it up and ran the AC only a slight pleasant fragrance was noticed. The bad smell was gone!

 

Thanks FlopTop04. Great DIY. so how do you tell when the 1st can is 1/2 empty?

 

Good question. It was a bit difficult to judge the weight of the can while the application hose was on and plugged in to the cars drain hose. If you have a postal scale or similar you could do a weight before and then again when you think it's close. The time you are dispensing the can is a good 40 seconds for each half, it takes a while. I just made a judgement guess by feel / heft. It was pretty close by the amount of liquid that dripped out each time.

 

I am neurotic( just ask my kids and wife) about NEVER starting the car with a/c on and ALWAYS turning off the a/c 5 minutes before i stop and just running air through the system to blow out all conditioned air but i enjoyed your DIY.

Well done. Great write up. Thank you.

 

What I have found out was if you ran the AC regularly, no odor was presented. In contrary, if the AC not being used or the car sat for long period of time, surely there is a smell. I sprayed a can of Lysol into the AC vents from time to time plus the usage of air fresheners helped.

 

Big can of beans works wonders as well !!

 

I used the Toyota product one time and it helped a lot. Recently, I wanted to do it a second treatment, but couldn't find the Toyota brand anymore. Instead, I bought a more generic product for cleaning evap coils, which is also a spray liquid that turns into a foam before melting and draining out. It's a lot less expensive. Once I've used it, I'll report back how it worked. I don't feel the need to repeat the "part 2" treatment which freshens the ducting, as I believe the odor is coming from deep inside the evap mixing box.

The smell was the worst when I first bought my 2008 SC in 2016. I don't think the previous owner practiced any of the practices/procedures to limit the accumulation of moisture in the evap box. Having owned Toyotas for decades, I'm aware of the propensity for these odors, so I routinely run my systems on fresh air when possible, shut down the AC a half-mile from home, and turn up the fan to high to help dry out the system. Generally, the odors have been diminishing in my four years of SC ownership, but not 100% yet!

I bought my 2001 Tundra in 2003 and it had the same issue. I had a auto-detailer run ozone through the system and it worked miracles! However, when I recently attempted to purchase an ozone generator on Amazon, they wouldn't ship it to California! I'm gonna see if I can get it shipped to brother's house in Nevada and pick it up there. Since the initial issue with the Tundra odor, I've prevented any reoccurrence simply by keeping the system as dry as possible (as detailed above).

 

Thanks so much for the excellent post, and especially for the pics! I live in the desert in West Texas, and not so likely to have the problem in my 2003. Users like you are what makes this forum so great.