A couple of questions re climate control

[StevenRB45]

When the windows mist up does pressing AC clear it?

One of the reasons mines never off is that the car seems to mist up pretty fast if it isn't on but ecomode seems to keep it clear even if it set to floor vents unless you've got 4 people on board in wet stuff and it's raining.

[amar1994]

When the windows mist up does pressing AC clear it?

One of the reasons mines never off is that the car seems to mist up pretty fast if it isn't on but ecomode seems to keep it clear even if it set to floor vents unless you've got 4 people on board in wet stuff and it's raining.

Not necessarily , screen can be defogged with warm air without use of AC  , but when the temps are around 10-20 degrees and you don't want it to blow hot air , then yes you need AC turned on . I can't turn it off, because i have crappy cabin filter LOL  and it's constantly on AUTO at 21 deegres 

To stay OT , mine has never shown ECO mode , it seems that those 1.6 PSA diesels don't have that option 

[red_imps_2003]

Hmm. To be honest I've never noticed whether having the aircon light on as part of the climate control reduces the misting quickly or not. As it has been the windscreen and driver/front passenger windows that have needed clearing (to see both ways at junctions and so forth) I've always just hit the rapid demist button (the one on the far left that activates the front vents at high fan speed and heating element in the windscreen at the same time) for a minute or two then knocked it off again.

On a related note, I had knocked the aircon button off for driving too/from work yesterday, just to get an idea as to whether there may be a noticeable impact on fuel economy or not, and I am sure it got switched on automatically. I can't be certain whether this was automatic or something I did, though. Does it do that if, say, the cabin temperature rises above that set on the display or as part of a cycle to reduce misting? To be clear, the climate control was on ('auto' light lit) but aircon was off (AC light not on) but appeared to come on itself sometime during my journey.

[StevenRB45]

When the windows mist up does pressing AC clear it?

One of the reasons mines never off is that the car seems to mist up pretty fast if it isn't on but ecomode seems to keep it clear even if it set to floor vents unless you've got 4 people on board in wet stuff and it's raining.

Not necessarily , screen can be defogged with warm air without use of AC  , but when the temps are around 10-20 degrees and you don't want it to blow hot air , then yes you need AC turned on . I can't turn it off, because i have crappy cabin filter LOL  and it's constantly on AUTO at 21 deegres 

To stay OT , mine has never shown ECO mode , it seems that those 1.6 PSA diesels don't have that option 

Previous experience suggests it's much faster to use AC than heat if the engine is cold. Also as you say you don't have to run it furnace hot to keep the car clear.

I'd not thought that maybe the eco function isn't on the 1.6 diesel! *facepalm*. Every day is a school day.

Hmm. To be honest I've never noticed whether having the aircon light on as part of the climate control reduces the .

On a related note, I had knocked the aircon button off for driving too/from work yesterday, just to get an idea as to whether there may be a noticeable impact on fuel economy or not, and I am sure it got switched on automatically. I can't be certain whether this was automatic or something I did, though. Does it do that if, say, the cabin temperature rises above that set on the display or as part of a cycle to reduce misting? To be clear, the climate control was on ('auto' light lit) but aircon was off (AC light not on) but appeared to come on itself sometime during my journey.

Pressing the demist button automatically switches on AC to take advantage of the dehumidifying function. Otherwise mine stays off unless switched on/auto is pressed even if it's over the selected temperature it just slowly turns the fan up to "the tempest" in an attempt to keep the temperature down.

[red_imps_2003]

Aye; I probably did something to activate the aircon (maybe tapped the auto button again without consciously recognising I'd done it). I will keep an eye on that one but am becoming more familiar with how it all works now, so big thanks to all who have contributed to this thread. It could be possible, as suggested above, that the eco mode simply isn't activated in diesel models or something (I know there's another thread below where somebody mentions it, so I may re-read that with the clarifications I have gained from this one). I am happy with how it is all working at the moment, now, though.

I've only owned this car through cold weather so far so am looking forward to see how well it maintains a comfortable temperature during warmer months. For the last couple of years my Focus only operated the top two fan speeds and the aircon was manual, so keeping comfortable was a constant fiddly process. I love the Mazda's feature to wind down all windows as you approach the car. I've never even heard of that before but can see it being handy.

Edit: There is further evidence that the 1.6d TS2 2nd gen specifically doesn't feature the eco mode on the thread I alluded to above at http://www.mazda3forums.co.uk/index.php?topic=4806.0.

[amar1994]

So to add on this , yesterday my USB stopped playing music and I could hear AC in Auto mode coming on and off, depending on my throttle and acceleration/cruising which means it does have some kind off ECO function , it just doesn't show it on the display 

[Willpower]

It will depend on if you have Manual Air Conditioning or  Automatic Air Conditioning  The two types are distinguisable by the control knobs.

For the moment I am assuming that you have the Automatic version.  So If you press the AUTO switch then selection of the airflow mode, air intake selector and amount of airflow will be automatically controlled.
You can then use the temperature control dial to select a desired temperature. Then press the DUAL switch or turn the front passenger temperature control dial, to control the set temperature individually for the driver and front passenger.

This means that you might hear the system cycling. This could be conceived to represent an ECO mode. But you are quite correct in that on your model/year there was no specific ECO indication in the display

[amar1994]

Yes it is Dual Auto climate control  , overall I'm quite pleased with mazda AC , it's miles better than one on my old opel/vauxhall astra 

[Engineer Andy]

I agree. As long as the temperature is comfortable I am not going to spend a fortune on diagnostics and repairs. The windows (all of them) do seem to mist up badly if I get in and my clothes are wet (or moist) but other than that I see no obvious signs of damp. Carpets, including the boot, feel dry and there are no unpleasant smells. I've experienced damp problems in two of my previous cars and it was decidedly grim after a while.   

The problem may be one of three things (that I can think of at present):
There may be a small leak which means the A/C system has to work harder to achieve the desired temperature when in cooling mode, hence why the 'Eco' mode light and console display isn't illuminated/shown;
The control system for A/C system and/or Eco mode is faulty so its always on 'full'.  This may include faulty temperature sensors, wiring, physical controls of the A/C and ventilation components or some part of the computer-controlled system (hardware or software);
A fault with the display - less likely given the light and the LCD screen are both affected.

Not sure what would be the most likely cause, and difficult to track down, even at the dealership.  I would caution against getting a re-gas unless absolutely necessary (if you can't get any cooling or it doesn't cool enough).  The reasoning behind this is that the wonderful EU, in its infinite wisdom, has decreed that all cars from now onwards shall be filled (new or regassed) with the refrigerant gas R1234a, which was supposed to be more resistant to leakages (less escaping into the atmosphere and polluting/causing global warming), but in reality is less resistant to leakages.  Even though legal refrigerant gases such as R410a and R134a are available to replace the same in our cars, I think they aren't allowed, its only in the construction industry that they are.  If you do go (at some point) for a re-gas, check with the dealership/garage what can be offered - if you can (legally) get the direct replacement using the original gas, my advice is to do so.

Sometimes the lack of usage of an A/C system, especially in winter months, can lead to the oils in the pipework drying up (they are circulated when the system operates to keep the components in good nick) which can lead to reductions in system performance and even failures.  As other have said, if you have climate controlled A/C, leave it on all year and just adjust the desired temperature to suit the time of year for your comfort level, leaving it on auto mode as much as possible.

Also, in winter, once a month (preferably once a week) run the A/C on full cold (min. temp possible, e.g. 16degC) after the car internal temperature has reached its normal level (say 20-21degC) for about 5 mins, to circulate the oils when its in cooling mode; similarly in summer, do the same for the heating function on its highest temperature setting (29degC), which should kill off most of the bacteria that can grow on the inside of the air ducts in wamer, humid conditions and cause that damp, musty smell and is a contributory factory in respiratory problems.  Doing so can be a bit of a phaff and uncomfortable, but is worth it if it means your car's A/C system lasts as long as the rest of the car.