glad to read this one, a lot of good info here. I remember when I had problem with AC and my mechanic told me I had to replace the blower motor so I purchased one from jcwhitney's site... this is where I get cheap auto interior parts for my Toyota Corolla.
The Toyota Highlander does have an external temperature sensor. In fact, you can pull up the temperature that the external sensor is reading on the display of the climate control system.
I don't think the system is behaving differently than intended. I think a lot of this discussion challenges whether the way that it is programmed is most appropriate or not. As with most engineering systems design, there are trade-offs and some different opinions on how those are best managed.
Naturally, in a fully manual system, those opinions become moot, because the user can operate the system the way they want to.
This control problem can be eliminated if the outside temperature is known to the temperature controller. A simple compare of inside to outsiide temperature will make the cooling or heating algrithm simple.
Good points, David. Unfortunately, the nightmare scenario you describe is becoming more common than the simple, intuitive controls of the past. I many cases, this added – unintuitive -- complexity doesn't seem to deliver additional value.
Carbon monoxide IS a serious issue with many people being overcome by high concentrations warming up cars and/or idling with the tailpipe obstructed.
Even when driving, Mr. Bernoulli comes into play. I had it happen to me years ago with bad body shop work leaving a small gap in the trunk lid seal where it sucked in tailpipe fumes that we could smell.
What sort of conspiracy do you think all the world's auto manufacturers are trying to pull on us? They're just covering themselves by using as much fresh air as possible. As you say though, that's only as good as the air polluted by the cars in front of you but hopefully that's diluted a good bit.
The mechanical systems were balky, the vacuum systems were complex and expensive. The electronic system is current technology and once they shake out the bugs, hopefully will work for years, ATC or manual.
I agree with the poster about the multitude of tiny buttons. How many people have to die in crashes just so the kids can have their gadgetry?
I fully agre that the older radios did indeed have all of the controls needed for a normal person to be adequately entertained in a car. After all, we are in a car, not an audio listening room. I have no expectations that they should sound the same.
Now, about the inflexibility of selecting outside air or recirculated air: I have heard that STUPID carbon monoxide litany for many years, and I have never known anybody who parks their car in a snowbank with snow plugging the exhaust pipe that is full of pinholes. MOst of my driving is not done while parked in a snowbank. At 35 or 55 MPH, most of the CO that arrives inside my car comes from the vehicles ahead of me, rather than my own vehicle. So the real truth is that the auto companies are inflicting on all of us a measure included soley to protect them from being sued by stupid people. So at least they should tell the truth about why they do things like that. Of course, presently it is hard to find a car with the simple HVAC controls, unless one looks at a cheaper import.
REgarding the one post about the problem with the broken cable, those cables were fairly simple to fix and also fairly simple and cheap to replace. And if one did not mind things not matching, universal replacement cables were even cheaper.
I have a 2004 Toyota Highlander. I find the automatic climate control as fairly intuitive and acceptable, but really no advantage over a totally manual system. The real disadvantage is when I ever will need to trouble-shoot it for repair. More complex, more to fail, harder to trouble-shoot for a repair.
The older automated climate controls were much more clunky and sometimes providing heat when you wanted A/C and vice versa. I am mainly talking about the old GM "Comfortron" and Ford automaticly vacuum controlled systems. I do not like them.
I also prefer the old radio controls that you could operate by feel, and not need to look down to see which of the 12 to 24 tiny buttons you are about to push. The remote steering wheel controls put some of the intuitive back into the control. For example: I drove a BMW 945 one time without having the owners manual. It was hard to figure out how to start, put in gear, or open the gas door. I never tried to get the voice command radio and navigation system working. I'm sure it would have been nice after learning the systems, but was a little bit of a nightmare without an owners manual; even though, I consider myself pretty savvy about cars and technology.
Even in industry, I prefer any control system that is more intuitive; rather than, some computer-interfaced system that requires a week with the operation manual to learn the software, firmware, operating modes, and special features. For example, some of the features are imbedded in the codes, accessable by holding on the right pair of two buttons for over 5 seconds to switch menus as indicated with a two to four alphanumeric code on the display (defined in the manual). This requires a review whenever you go back to the old equipment and heaven help you if the manuals are lost.
Interesting, Michael. For most popular music this is already covered by the recording process. It is probably only classical music that would require equalization between loud and soft passages. As for classical, it never occurred to me to equalize loud and soft. Seems like that is something I'm not supposed to mess with.
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