AWD in cx5 and the use of wiper.

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CX-5 AWD, 2017
I was wondering if the drive on a highway on a rainy day with wipers on constantly would automatically set the AWD in action and there by increase fuel consumption and transmission wear and tear. They do mention that one of the factors that triggers AWD is the use of wipers (others being, road incline, low temperature, wheel slippage, wheel turn angle, etc). There is even a you tube video from Australia on off road cx5 driving where the guy has the wiper on during the whole climb even though there is no rain in sight. Is he forcing a AWD in action?
 
You can’t measure the increase in fuel consumption the wipers make. It is minimal. It only alters the mapping of the AWD and how it engages.
 
I was not referring to the fuel consumption increase by the wipers (which is naturally negligible) BUT I was referring to the increase in fuel consumption due to induced AWD by the use of wipers in a rainy situation. In a normal situation it works in 2WD mode but with rain and wipers being on it may get induced into AWD, which in turn can increase fuel consumption.
 
any increase in load on the engine is going to increase fuel usage. However, w/o Mazda Engineers to explain how the wipers change the application of the AWD system, it is tough to say how the AWD system is staged in stand-by or "predictive slip" mode. I would think that keeping engine load low or rpms down and leaving off "sport mode" would/could minimize fuel consumption when the wipers are on.

With that said, we got the best mpg on our 04 Pathfinder when in 4H (4 spd auto). However, that involved driving at (averaging) 30-35 mph for about 8 hours [stuck between ice storms traveling East on I70]. Despite being in 4H, the load on the engine was minimal and we hit an all-time best of 23mpg on that tank; which was more or less that whole day's worth of driving.

This should prove true for most, if not all ICE cars. I believe that 40-45mph (w/ minimal brake usage) is the optimum speed to achieve the best/highest mileage. [NOTE: I have not tested this theory in the CX-5]

I read somewhere that wind resistance quadrouples as speed doubles.
 
I was wondering if the drive on a highway on a rainy day with wipers on constantly would automatically set the AWD in action and there by increase fuel consumption and transmission wear and tear. They do mention that one of the factors that triggers AWD is the use of wipers (others being, road incline, low temperature, wheel slippage, wheel turn angle, etc). There is even a you tube video from Australia on off road cx5 driving where the guy has the wiper on during the whole climb even though there is no rain in sight. Is he forcing a AWD in action?

Yes from what I understand, that is a way to force AWD. Another idea I had was adding a switch that sent a false freezing temp reading to the ambient temp sensor.

The transmission, transfer case, prop shaft is still always turning regardless of AWD in use or not. The rear diff would be the only thing getting "added wear and tear"
 
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OP, as was discussed in another thread a while ago you are correct,,,,BUT,,, only partially so. When wipers are on there is more of a torque split towards the rear but it is not set at 50-50. I do not know the split but yes, there is more torque sent rearward with wipers on.
Also, at highway speeds vs city speeds the torque split is also different.
So, to answer your question, yes, your mileage will ever so slightly change when your wipers are on but not like a fully engaged system.

Also, that video you watched was correct, having them on helps more torque transfer but I'm guessing that the torque split was full on already based on his wheel slippage, vehicle angle, throttle, etc already.
Your research and looking for old links was very good. More people should be like you when checking/researching this vehicle!

As Mazdadude above stated, everything is already turning, it's just the clutch pack in the rear diff that gets engaged in a range of, shall we say, hold as it's a variable system.
 
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To add another layer of complexity - what if you are using the rain sensing setting. And you get intermittent wiper action due to mist or light rain. Does the AWD programming have a different response versus wipers on slow or fast? To me it's unclear how the wiper status is mapped to the AWD. Practically, it doesn't make any noticeable difference in how I feel the car respond. Fuel consumption does appear to increase a bit in wet weather. But I mark that up (guess that) it's due to different driving behavior and more drag when there is enough water on the road to create drag on the tires pushing water aside.
 
In normal conditions even with rain, the awd does not stay on. It is on for that instance you need it. Going around a curve, uphill, downhill etc. The system works to give you confidence while driving. This is what I have learned and was explained to me. In snowpack conditions then yes the system will stay engaged. On a wet day going around a corner, it might send 20% power to the rear just for that corner then back to front wheel drive. The wipers are just one part of the info that the computers are using.
 
I was wondering if the drive on a highway on a rainy day with wipers on constantly would automatically set the AWD in action and there by increase fuel consumption and transmission wear and tear. They do mention that one of the factors that triggers AWD is the use of wipers (others being, road incline, low temperature, wheel slippage, wheel turn angle, etc). There is even a you tube video from Australia on off road cx5 driving where the guy has the wiper on during the whole climb even though there is no rain in sight. Is he forcing a AWD in action?

You have to use the wipers in the rain.

The all wheel drive system is always active, whether it's raining, or not.. The trans is always sending torque to the rear differential, but a slip clutch on the front of the rear diff normally slips, applying ~5% of available torque to the rear diff. When conditions dictate, including using the wipers, the rear clutch tightens and slips less, applying more torque to the rear diff/wheels. Nothing you do with the wipers, or other controls will affect transmission, driveshaft or rear diff wear. Change the lubes periodically.

See Item 5.

ac5uuw00000869.gif
 
You have to use the wipers in the rain.

The all wheel drive system is always active, whether it's raining, or not.. The trans is always sending torque to the rear differential, but a slip clutch on the front of the rear diff normally slips, applying ~5% of available torque to the rear diff. When conditions dictate, including using the wipers, the rear clutch tightens and slips less, applying more torque to the rear diff/wheels. Nothing you do with the wipers, or other controls will affect transmission, driveshaft or rear diff wear. Change the lubes periodically.

See Item 5.

ac5uuw00000869.gif



technology_safety_active-safety_i-activ-awd_3rd-row_img_1601.ts.1602150246028730.gif


Here is the official Mazda I-ACTIV AWD as explained by Mazda.
http://www.mazda.com/en/innovation/technology/safety/active_safety/i-activawd/
 
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Thank you all for the reply to my simple (or not too simple question). Since we do not know the weighting of each parameter (incline vs wheel angle vs slippage vs wiper use vs temp. etc.) and how many of those are needed to activate the rear drive and to what extent, we might just be speculating. Let us hope the brain in it (the programming) is intelligent enough to make the right choice. It would be academically interesting to know a little bit more about this so called intelligent system in detail and not just the company's usual brochure block pictures. Talking of these impressive pictures the Toyota RAV 4 has a live screen picture showing you how the power is being split between the front and rear during AWD. We do not know if it accurate but it certainly impresses people and not to forget that AWD lock button in RAV4.
 
Thank you all for the reply to my simple (or not too simple question). Since we do not know the weighting of each parameter (incline vs wheel angle vs slippage vs wiper use vs temp. etc.) and how many of those are needed to activate the rear drive and to what extent, we might just be speculating. Let us hope the brain in it (the programming) is intelligent enough to make the right choice. It would be academically interesting to know a little bit more about this so called intelligent system in detail and not just the company's usual brochure block pictures. Talking of these impressive pictures the Toyota RAV 4 has a live screen picture showing you how the power is being split between the front and rear during AWD. We do not know if it accurate but it certainly impresses people and not to forget that AWD lock button in RAV4.

Yes it would be great to know more. Mazda is always surprisingly forthcoming on how the systems operate, and maybe you can ask them for more info than the MAZDA website I linked to.
 
The rear differential clutch is electronically modulated, ForScan is able to read it's duty cycle in (almost) real time. The readings look like coming a couple of times per second, but the modulation frequency is much higher.
In our '15 the default duty cycle is always between 6 and 12%, meaning that the rear axle is getting 3-6% of torque.When wiper's are on, duty cycle is closer to the higher value of the range, but that's it. It goes way higher into 70s in the snow though.
 
Getting back to the original question about the impact of greater AWD activation on fuel economy, I would also suspect that the increased drag from the wet road would probably have a greater impact on fuel economy than the increased torque going to rear wheels?

So how you would you isolate the impact on fuel economy of the rain induced drag from the AWD activation? I dont think you could do it....
 
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Increase the rpms to increase the power available for awd.. you can tell the difference if you are attuned to how your car performs and feels under certains rpms etc. Rapid throttle/ downshifts are going to increase wrong wheel slip and increase your rear transfer.
 
Increase the rpms to increase the power available for awd.. you can tell the difference if you are attuned to how your car performs and feels under certains rpms etc. Rapid throttle/ downshifts are going to increase wrong wheel slip and increase your rear transfer.
I've driven around with my rear on lock a few times and highway mpg doesn't seem much different.
 
I think I mentioned this in post years back but wonder if rear wiper is connected to system? I never tested... It would be nice to have this option if turning on the front wipers was undesirable for current weather.

EDIT:

I believe this is referenced video from poster here from Canada.

 
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How did you lock your rear wheels in CX-5?

pull dsc 30a fuse (not for noobs, you can get sideways with aggressive driving (easily with a wet road) and the stock monster truck height might give you some bad feedback when that happens)
 
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