Is it possible to calibrate the AC climate control thermostat?

[thx1200]

Ahh... Fall and Spring -- the two seasons with the finest weather!

I live in the south, so during the summer (which is when I got my Smart), I pretty much kept the AC to the bottom notch -- the one below 60 -- which basically tells the system to blow the coolest air possible all the time (and turn on recycle air automatically when more cooling is needed -- awesome).

Now that it's fall, this is the time of year I generally keep the AC on to combat the humidity, but mix a little heat to make it comfortable.

What I've noticed is that at the 60 degree notch, just one notch above maximum cool, the blowing air is too warm for me! I'm practically sweating. it's certainly not giving me 60 degrees. I'd guess the blowing air is 65 at the lowest, which means when you factor in the heat from the sun that the cabin is maybe 70-75 (definitely nowhere near 60). In my house I have the AC set at 70 and it's comfortable for me, so there's no way my Smart is doing 60.

I could take it to the dealer under warranty, yes, but I'm just so much of a do-it-yourselfer! Does anybody know if there is a way to calibrate the climate control to make the temperature range cooler? It's probably deep in the bowels of the car's computer, but I'm hoping there's just a little potentiometer hidden somewhere for me to fiddle with to adjust the interior thermometer.

I'm cold natured and I live in the south, so I'm not too worried about it not being hot enough in winter. :-)

[Old smart]

There is a little infrared eye at the bottom of the distribution control which regulates (or assists in regulating) the temperature - an electronic thermostat. Whatever it "sees" is what it calls for. Make sure that there isn't something in its line of sight that is confusing it.

[forestacademy]

Oldsmart is refering to this thingy

[thx1200]

Thanks a lot! I'll double check when I drive home tonight. I'm pretty sure nothing is in front of it, though. Maybe I need to put a mirror in to reflect the infrared to my overheating torso so it cools me down more. ;-)

EDIT: I wonder if I could rig in a little potentiometer to affect the current returned by the "eye" to fake the Smart into using a different temperature that's more comfortable for me. HMMM... :-)

[jwight]

...(and turn on recycle air automatically when more cooling is needed -- awesome).

With two smarts now, I've never seen the A/C go to recycle automatically, even on the hottest days.

[MB DNA]

OK, are we sure that the "thingy" isn't BIG BROTHER watching?

I though it was a light sensor that simply detects sun up or sun down?

Most other vehicles have such a thingy mounted on the dash and it senses day/night and makes minor adjustments to the air conditioning.

And in the South, having your thermostat set at 60 degrees the system will never cycle until you see snow on the ground as this is a very small engine with an even smaller air conditioning system.

[rfernatt]

Originally Posted by jwight

With two smarts now, I've never seen the A/C go to recycle automatically, even on the hottest days.

I can vouch for the auto recycle functionality. However, I've never been in a car with an auto climate control that actually worked in any useful fashion (Subaru, Honda, etc.). It always just seems like a gimmick that never pans out as advertised and the smart doesn't seem to be any different. Just give me a temp slider, vent, and fan control. I always leave the temp slider in the lowest setting on the smart and just change fan speed/vent selection to suit.

IMHO, smart would probably be better off saving a few bucks by cutting this functionality altogether (it is a small economy car, after all) and putting it into something more useful like a longer standard warranty, better OEM stereo, factory cruise unit, more color choices, improved trans, etc.

[ssppxyz]

Originally Posted by jwight

With two smarts now, I've never seen the A/C go to recycle automatically, even on the hottest days.

Odd...My 2009 does it regularly when the differential between setpoint and return (cabin) temp is high.

It cycles to recirc and back to fresh when the cabin temp starts off very warm/hot and then cools down. This cycle will repeat if the cabins heats back up again for whatever reason (parked for a bit, windows down, etc.).

[thx1200]

Originally Posted by jwight

With two smarts now, I've never seen the A/C go to recycle automatically, even on the hottest days.

The light doesn't light up, but it engages (the fan volume will increase). You can confirm this by pressing the recycle button and then pressing it again (notice how much quieter it gets).

After it gets closer to temp, it will turn off. I've only seen this happen on max (notch below 60). It never does it when it's anywhere in the thermostat's temperature range of 60-80 for me, but again that's just me.

Next time it's 90+, give it a try. :-)

[thx1200]

Okay so I double checked the infrared and nothing is in the way. I guess short of anybody knowing any way to calibrate the sensor, I'll be giving the service center a call to see what they say.

rfernatt - I completely agree. It never seems to work right. I was hoping Smart's would be better since I find the car otherwise is, despite it's economy, really very high quality. They could at least have an "auto" switch that toggles between the old school slider and thermostat mode.