2020 GT Cylinder Deactivation App View

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GA prior 16 CX5 GT
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20 CX5 GT + Prem
My 2020 GT Premium has a screen in the Mileage Application that displays the Cylinder Deactivation Status. Even at 70 mph when you go down a hill it turns the light off #1 and #4. If the hill is steep it will eventually turn off the light on all 4 cylinders I guess with a fuel cut off. At the bottom of the hill all four lights come back on at the same time. The story of CD working only under 40 mph does not seem to apply to this model. It is also getting about 2 mpg better with a new tight engine vs my old 2016 GT that has 60,000 miles on it. I am unable to detect when CD is active except by looking at the screen. So far so good...
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
My 2020 GT Premium has a screen in the Mileage Application that displays the Cylinder Deactivation Status. Even at 70 mph when you go down a hill it turns the light off #1 and #4. If the hill is steep it will eventually turn off the light on all 4 cylinders I guess with a fuel cut off. At the bottom of the hill all four lights come back on at the same time. The story of CD working only under 40 mph does not seem to apply to this model. It is also getting about 2 mpg better with a new tight engine vs my old 2016 GT that has 60,000 miles on it. I am unable to detect when CD is active except by looking at the screen. So far so good...
Thanks for observation on cylinder deactivation of your new 2020 Mazda CX-5 GT Premium. So there’s a CD app on 2020 CX-5 2.5L which will help the driver to know the status of the CD. IMO Mazda may have reprogrammed the CD activation criteria for newer MY’s but doesn’t provide updated info to the consumers.

Or the observation you had is only designed for engine brake with CD during down-hill. I guess you can try to observe if the CD would be activated during the highway cruising speed above 50 mph on flat surface. And when cylinders deactivated on designed cylinder #1 and #4, the operation is different from “turning off” the cylinder #2 and #3 as the valves on cylinder #2 and #3 will never be kept closed during their “deactivation” period.
 
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GA prior 16 CX5 GT
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20 CX5 GT + Prem
At idle I have not seen it in CD yet, you may be hearing AC compressor kicking in or something else?
 
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CX5 GT
Its the rpm and torque that matters not speed. We discussed it few times in the past, there is a diagram for the range.

Also after the pcm update I noticed aprox 2 to 3 mpg better during CD-enabled consitions on my 2018.
 
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CX5 GT
may be infotainment update..since its pcm controlled although I dont remember seeing any option for cd exposed in the infotainment linux parameters that I saw when exploring aio...
...who knows..

Gaxibm, what is your version of the infotainment on the 2020?

Thanks.
 
My 2020 GT Premium has a screen in the Mileage Application that displays the Cylinder Deactivation Status. Even at 70 mph when you go down a hill it turns the light off #1 and #4. If the hill is steep it will eventually turn off the light on all 4 cylinders I guess with a fuel cut off. At the bottom of the hill all four lights come back on at the same time. The story of CD working only under 40 mph does not seem to apply to this model. It is also getting about 2 mpg better with a new tight engine vs my old 2016 GT that has 60,000 miles on it. I am unable to detect when CD is active except by looking at the screen. So far so good...
Do you notice a slight jerkiness when transitioning from no pedal press to light pedal press? Mainly from first to second gear at low speed. When that happens, I could see the 4 cylinder changing from all inactive to all 4 active.
 
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2018 CX-5 Sport
Do you notice a slight jerkiness when transitioning from no pedal press to light pedal press? Mainly from first to second gear at low speed. When that happens, I could see the 4 cylinder changing from all inactive to all 4 active.
I think you are feeling the transmission clutch locked but the speed of the car isn't exactly matching to the speed of the turning transmission then the transmission jerks. Generally it only happens in 1st gear. If you press the gas pedal a little harder from no pedal press it shouldn't jerk.
I don't think you can feel the transition of CD because the engine has no load on it when CD kicks in or out.
 
I think you are feeling the transmission clutch locked but the speed of the car isn't exactly matching to the speed of the turning transmission then the transmission jerks. Generally it only happens in 1st gear. If you press the gas pedal a little harder from no pedal press it shouldn't jerk.
I don't think you can feel the transition of CD because the engine has no load on it when CD kicks in or out.
Thanks for your reply. Would you say this is a common behaviour and considered normal? I could also hear a "tick" noise when this happens. And yes, mainly in low gear and low speed only
 
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2018 CX-5 Sport
Thanks for your reply. Would you say this is a common behaviour and considered normal? I could also hear a "tick" noise when this happens. And yes, mainly in low gear and low speed only
I can get mine to do it, which I consider normal, but I don't know if your car is normal or not. It is hard to gauge the severity from the message board, it's best to ask your dealer/mechanic when you get your next oil change.
 
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CX5 GT
Do you notice a slight jerkiness when transitioning from no pedal press to light pedal press? Mainly from first to second gear at low speed. When that happens, I could see the 4 cylinder changing from all inactive to all 4 active.

This is normal and not related to the Cylinder deactivation system. All cylinders are off because this is how injection works, more specifically the injection fuel is cut off when you release the gas pedal. Mazda just made the graph show off in this case but it's different than CD.

What you notice with the jerkiness is actually the transmission/computer not sure whether to go 1st or 2nd gear on very low revs and in between. Quite common at almost idle revs and car moving slow. Switch the sport button in this case and you would see no such behavior. The transmission will stick with 1 gear for longer, more revs.
 
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2018 CX-5 Sport
Do you notice a slight jerkiness when transitioning from no pedal press to light pedal press? Mainly from first to second gear at low speed. When that happens, I could see the 4 cylinder changing from all inactive to all 4 active.
DarkStar, if possible, make a video of the behavior and the sounds. Without a video, forum members think jerkiness and clicks are describing different things. For example I think it describes the clutch locking with the car rolling faster and slower while in 1st gear than the trans is turning, and cz5gt thinks it describes the shifts hesitating because the speed is in between the programmed shift points, and sskali thinks it is caused by the opening / closing of the throttle valve.
 
Guys, I was given the attached TSB from another member in this forum.

My car was made in Nov 2020 in Japan and I live in NZ. Hard to tell whether mine is applicable but still a good knowledge to know nevertheless.

I did find this YouTube vid below explaining how Mazda introduced a clutch on their automatic tranny, so this may have contributed to it as well?
 

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