We have a 92 SC300 and I was wondering what that little black dome thing thats on the dashboard facing the sky on the drivers side is for? I know its a pretty bad description, but thats all I can think of. If anyone know please tell me. THANKS

 

I was thinking that last night as a matter of fact. I think it has something to do with the security system... please correct me if im wrong.

 

Shoud it blink red? Because I've seen cars that have red blinking lights when the security system is on.

 

I don't own an SC yet so I can't say for sure, but what you're describing sounds like the receiver for the keyless entry. Many other makes of vehicles have these mounted on the dash, close to the bottom of the windshield.

 

I think keyless entry receiver is installed on the side of rear seat(passenger side).
I thought it's day/night light detector but I guess not. I wonder what that is..

 

The keyless ECU is located in the panel next to the rear passenger seat. I was under the impression that the keyless antenna is on the defrost wires. It is supposed to be the weak link in the keyless entry, but have yet to figure out how to fix it.

 

How do the auto headlights sense light and dark?

 

i dont know what it is but probably not a light sensor since they didnt have em in 92... and the auto head lights use a photo potentiometer which changes its resistance based on how much light is hitting it and acts as a switch.. they are also used in
outdoor lighting applications

Adam

 

Solaras have two of those black thingys, one in the same spot where ours is, and one on the passenger side of the dash. i kno that the one on the passenger side is for headlights to turn on when it gets dark in case u forget to turn them on. dunno wat the other one is for.

 

One of those circular sensors is an ambient light sensor for the auto-headlights. If you're driving at night and shine a flashlight onto it, the headlights click off. I believe the other is a keyless entry infrared eye.

 

The driver side black dome is the ambient temp sensor for your climate control. It makes adjustment based on temp and glare from the sun. For people that have inspection stickers directly in front of the dome, you have been tricking your climate control into thinking that it is always cooler than it is because the sticker provides a sunshade so to speak. I got my inspection sticker moved 3" to the right for that reason. Made a difference.

 

The black thing is where the sensor goes on the Japanese right hand drive cars. Remember, everything is reversed, including that.

 

Yes it's the temp sensor in a sense. It detects the amount of direct sunlight hitting the dashboard, and compensates the airflow from the A/C to match.

The actual temp sensor is on the dashboard, it's a little like 1" by 1" square vent with little slats. Just below the ignition key.

The automatic climate control system will still function fine if you unplug that one up on the dash, but you may get warm for a few mins if you go from dark to light (i.e. tunnel etc) because the actual temp sensor has to detect that.

As for the one in the dash, if you disconnect that, the auto a/c system will push out only heat. That one has to be connected.

In either case, if you put the A/C on manual mode, it works fine.

SR