I'm having some trouble regulating the cabin temp in my 2002 SC430. It's cold outside here in Atlanta (in the 30's in the morning) and for some reason even when I have the temp set on 66 (not in auto mode) the cabin gets really hot! If I drop it to 65 the AC comes on. It's just weird.

Not sure where the temp sensor is located (will check the manual for that) but was wondering if anyone else has experienced a problem regulating the cabin temp. If put it the auto mode -- it ramps the fan up to high and cooks us all inside the car.

Thanks for any thoughts or ideas.

-gene

 

I haven't double checked but I believe the SC has a sensor that can be cleaned just like the GS. Here is a link on how to clean the sensor on the GS.
https://www.clublexus.com/forums/gs-...mp-sensor.html

 

Thanks for the link. I'm going to see about cleaning the sensor. That may help. My wife complains about the same thing in her 2001 LS430. Guess some age has taken its toll.

-gene

 

I have a similar issue... the climate system seems to have a mind of its own... I'll look for the sensor and will also follow this thread carefully.

Thanks for posting!

 

The sensor inlet is located on the drivers side panel above your knee/thigh it is a small louvered vent about an inch square. Mine was full of lint when I purchased the car. Make sure it is clean and open. Use a vacuum to clean it. If required, use a toothpick or similar soft tool to loosen the dirt.

If this does not correct the problem, you may need to follow the vent tube down to the actual sensor. Open it up and clean it out or replace it. Sorry no pics.

Someone posted a link to a gs with this issue and they look the same as the sc

 

So you don't necessarily have to remove the sensor to clean it, as was shown on the GS DYI?

 

If the sensor is the problem you will need to open the system and either clean and/or replace the sensor.
If the inlet in the dash is completely blocked with lint the cabin air cannot get to the sensor.

Here is how it works, cabin air is drawn into the small vent, that air travels through a tube until it reaches the sensor, the sensor measures the air temperature and adjusts the heater valve to control the heater temp to either warm or cool the cabin.

 

Here are two pics of the sensor which is located just above the drivers right thigh. You will need to remove three bolts on the lower panel which will then give you access.




Dirty...





Clean and still wet. Yes I used water. It will not hurt it.

 

Just to be safe, you should use electronics / MAF cleaner. Do you MAF too since you bought the can

 

It is a sealed sensor, but if it makes you feel better use the Mass Airflow Sensor cleaner. I live in Florida with plenty of moisture in the air...the sensor gets wet.

 

Thanks for the pics and the location. The dealer thinks they messed it up when they did the airbag recall. Hey, if they want to fix it -- I'm for that

 

Update: I noticed this issue with the cabin temp AFTER the dealer did the air bag recall. Took it back today and they admitted to having messed up the sensor. They replaced it (NC of course) and all is well.

On another note -- as I was driving to the dealer the engine light came on. That seemed odd to me with only 20K miles on the car -- even though it's a 2002. They claim the code is related to an O2 sensor on bank 2 -- to replace I'm looking at $520. I've had this issue with my old RX300 that had 100K miles on it -- but with just 20K -- I'm really suspicious.

Any thoughts -- could it be related to the cabin issue? I'm doing nothing about it for the moment.

Gene

 

Is there any chance someone filled it up with regular gas? Low octane will cause the light to come and call out an O2 sensor.
Did you fill up at a station you normally do not use?

 

I will check on my sensor and clean it too! Thanks.

 

Bgw, I've run with regular gas for years without any issues. Gas mileage is about the same but acceleration is slightly less but other than that, I've had no issues in over 80k miles. (No knocks either.)