[drtravel47]

Why do I have press the defroster button on the steering wheel twice to turn it off? The first press turns on the AC, the 2nd press turns off the AC and the defroster.

Why doesn't pressing the defroster button, once the defroster is on, just turn it off?

AND---speaking of defrosters. I went to the dealer and asked him if the bottom window of the 2 rear split windows was connected to the rear defroster. I can see the 'lines', but it never seems to work. He checked it and said current is flowing there. However, the unit times out (after 20? minutes), with the top totally defrosted/fogged and the bottom still hasn't done squat. Is this common?

 

[Tideland Prius]

I'm not sure what your question is for the front defroster works fine for me. Once - on, press again - off/back to previous setting.


The lower rear window does have heater wires. The "frost" may just be the dirt on the outside of the lower window

 

[DanMan32]

Some have found that the early 04 productions did not have the lower wires connected. The way the connections look on mine, they seem spliced in, so Toyota may have overlooked the connection in early production.

When you are turning off the defroster, are you doing it with the Auto button? That may do what you are describing.
When the HVAC is in a non-auto but on state, pressing auto may turn it back to full auto, but then subsequent push will put it to full off.

 

[drtravel47]

defroster button

Dan,
I'm turning it off the same way I turned it on----using the button on the steering wheel. But when try to turn it off, the AC/Auto comes on. I have to press it again to turn it and the AC/Auto off.

Thanks

 

[DanMan32]

I tried playing with the defrost (both front and back) the other day.
The front defrost will suspend AUTO and cause the AUTO light to go off, but pressing defrost again would revert HVAC to go back to the state you had it before you activated front defrost. Pressing yet again would reactivate front defrost, again suspending HVAC AUTO and turning off the corresponding light.

The rear defrost did not affect the HVAC at all.
My car was mfr'd June 04. Earlier models may have different behavior programmed.
Also, the HVAC function may be configurable by the dealer.