When switching on the outside air intake and also depressing the front windsheild switch, I experience the air from the vents to be unusally cold. Promptimg me to believe the air conditioner is activated even tho the AC light is not on. I mentioned this to the service department at my local Toyota dealership and the service guy said that the defrost switch activates the condenser. I must also add that the setting for temp is set to Lo and the Auto switch is not on. Has anyone experienced this? Is the sevice guy correct? I hesitate to believe he is correct. Thanks, Nick
As per page 274 of the Owner's Manual: Press (the front defrost button). The air conditioning system control operates automatically. Recirculated air mode will automatically switch to the outside air mode. Also mentions automatically on page 278 when in cold weather and the use of defrost. From what I understand, by pressing the A/C button (indicator on) it forces the use of the air condition but otherwise it is up to the ECUs (in auto) to determine its use (without the indicator coming on).
I think spiderman is almost right. Front defrost on: A/C will run automatically - most likely on, since if you're trying to defog, that means the humidity is high, and the car has a humidity sensor. Front defrost off, A/C light on: A/C will run automatically when needed, depending on the humidity and temperature. If you're heating in the winter, for example, I don't believe the A/C will typically come on. Front defrost off, A/C light off: A/C will not run.
Oh and just to add to all the responses here, because you were in LO, when you activated the front defroster, essentially it's MAX COLD with A/C blowing at the windshield. The defroster will remember your temperature setting.
