Sc400

[Bandit]

I have not been driving my 93 SC400 that much and noticed that I have a stale order coming from the heating ducts. The odor goes away if I turn on the AC. But as soon as I turn the AC off, the odor returns.

Is there a drain for the heating circuit that may be clogged and allowing moisture to be trapped in the duct work that would cause this odor?

There is no smell of antifreeze, so I do not think the heater core is leaking. It could be the condensation from the AC unit that is leaking into the Heater circuit.

Any help or suggestions would be greatly appreciated.

[over40driver]

I was over at TeamLexus website, and there was a service bulletin to the effect of if you are in a humid area you may have a odor when turning on the a.c., but it did not say what to do. I have sprayed a product called OZIUM, an air sanitzer in the air intake ducts by winheild with a.c. running to remove smells. ;)

windsheild that is.

[Bandit]

There is no odor with the AC on. The odor appears when I turn off the AC and am using the heat circuit.

Thanks for your reply!

[Air Force Rascal]

There is no odor with the AC on. The odor appears when I turn off the AC and am using the heat circuit.

Thanks for your reply!

You may want to check out the Cabin Air Charcoal Filter that is located up under the passenger side in the air duct....may need changing

Good Luck

[j_lee84sc]

there is a tube under the evaporator(located under and behind glove box) that drains the condensation out of the car, you can see the tube from under the vehicle passenger side. might be clogged. cabin air filter may need changing. there is a possibility that the motor that opens and closes the the vent to the outside of the car has stuck letting water and such in. try turning the ac on high with recycled air, then hit the button to change to fresh air. if there is no change with the amount of air comming out the motor may be out.

[Pirate]

I had the same problem with my 95' SC400. The odor is eminating from the air conditioner evaporator.

Lexus published a technical service bulletin # AC001-97 On Sept 12, 1997. It details how to clean the evaporator. I took my car to the local Toyota dealer (closer than Lexus) and had the evap. cleaned for $65.00

this ended the odor problem for the time being but I think it will re-occur sometime down the road.

[Randerso]

I have not been driving my 93 SC400 that much and noticed that I have a stale order coming from the heating ducts. The odor goes away if I turn on the AC. But as soon as I turn the AC off, the odor returns.

Is there a drain for the heating circuit that may be clogged and allowing moisture to be trapped in the duct work that would cause this odor?

There is no smell of antifreeze, so I do not think the heater core is leaking. It could be the condensation from the AC unit that is leaking into the Heater circuit.

Any help or suggestions would be greatly appreciated.

It is important to get your AC evaporator cleaned. The odor is from mold forming on debris that collects on the evaportor. The condensate drain hose may, or may not, be clogged for this to happen. If left alone it is likely that the evaporator will develop a leak from corrosion forming under the debirs. Sometimes refrigerant oil seeping from a very small leak in the evaporator also causes the odor. Please post how the cleaning goes and what it costs you.

[BMAN1113]

I used to have a musty smell coming from my vents. Then my A/C quit blowing cold. I took it to the Lexus stealership and they said my evaporator coil had sprung a leak. $1450 later I have an ice cold A/C and, sure enough, the odor is completely gone. I guess not cleaning the coil cost me big. Wish I had known a couple of years ago.