Shut off TCS for a day!

HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
thanks. changed it..
I hate to be a nag, but you should include the trim in your caption for future discussions to indicate which engine you have. For trims where both engines are offered a turbo indication there or in the post would help in the future.

Anyway, getting back to your question, I can say with high confidence that TCS OFF in a conventionally aspirated 2020 does not turn off cylinder deactivation because I have the same year/engine and I've tested it.
 
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2020 CX5 AWD
I did about 70 miles of back road driving and testing today, comparing TCS off vs. on. Some of that was without my wife telling me to stop fooling around. ;) My version of the vehicle in conveniently captioned at the upper left. :rolleyes:

One more preface: my PCM was updated in June 2021 which I suspect had a minor alteration to the torque curve which sharply reduced my lugging issues. Results may vary with earlier or later PCM versions of the captioned vehicle. Other years, trims, drive trains may vary.
  • The TCS OFF switch disables Lane Keeping / Lane Departure as the manual states. That's per the lane display in the right dash pod showing the vehicle always planted in the middle of the lane while driving over lines known to trigger it. No steering wheel vibrations or lane adjustments. The LK/LD disabled warning light does not appear on the dash, which seems odd.​
  • TCS OFF does not disable radar cruise as reported for the 2017 Mazda 6 with DSC OFF. This was verified by cruising up on a slower vehicle. This is consistent with the manual which makes no mention of such disabling.
  • TSC OFF does not disable cylinder deactivation. That's confirmed in seeing the real time gas mileage monitor jump to 60 mpgs or even bury at 80 mpgs with cruise off at a steady 50 mph with light gas and the cylinder monitor showing two cylinder operation.
  • I have not attempted to ascertain affects on Dynamic Stability Control, Smart Brake Support or Smart City Brake Support. Those tests would be potentially dangerous, or certainly so in testing differences in stability control performance. At least the manual doesn't mention any affect on these systems with TCS OFF but I wouldn't bet my life on it.
  • The manual states system overrides of driver inputs are altered with TCS OFF in manual shift mode. I did not test it. I don't use it. Those days are behind me. Be aware and check the manual for details if you use the manual shifter.
  • I find no difference in vehicle performance and shifting except for one note: TCS OFF has the vehicle do what it does with slightly less gas pedal pressure in getting up to speed. That's not be confused with a semi-sport mode since it revs about the same to it's shift points when adjusting pedal pressure for the difference. If out of habit I work the gas as normal in TCS OFF mode, the vehicle seems friskier getting up to speed, but that's really a performance illusion. If I add a little more gas then usual in normal mode, it behaves the same as TCS OFF.
  • In an unscientific monitoring of gas mileage on a 40 mile round trip with TCS OFF, a trip I make frequently with a good sense it come in around 28-29 mpg with TCS on, the difference is negligible or non-existent. Given less gas pedal pressure in getting up to speed with TCS OFF in daily driving mode I find this surprising, but it is what it is.
  • I need more hobbies.
  • I need more hobbies.
Agree..
 
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2018 Mazda CX-5 Touring
my bad then, I thought that the lugging and surging were kind of the same issue that we all know the car has with the shifting.
I dont have the fix done (my 3/36 warranty has expired anyway) so I cannot comment on real live experience with the car and the TSB fix for surging.
Most of my surging was fixed after the CD update but again mine is 2018 with Denso PCM.
Was thinking of applying the latest PCM update myself but with the TCS discovery I am happy overall so no updating for me for now.
Its like a different car now :) just have to not forget to turn the TCS off or find a way to turn it off upon start automatically.
Powertrain warranty on an 18 is 5/60. Bumper to bumper is 3/36.
 
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CX5 GT
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not covered for free after 3/36 according to the tsb.
 
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Phoenix
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2021 signature
What am I missing? Where does the above say that indicates that a power train issue isn't covered up to 5yr/60k
 
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CX5 GT
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there are different warranties.
There is also the Federal emission warranty on top of the above. Different repairs are covered under different warranty per Mazda discretion and are mentioned in each TSB explicitly.
All the rest is good will more or less whether by the dealer or Mazda US Corporate.
 
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2018 CX-5 Sport
About the 3-year/36K mile roadside assistance program, will Mazda still assist but charge the person for the assistance?
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
During the Thanksgiving Holiday we drove our 2018 Toyota Yaris iA (Mazda2 in disguise) from San Jose to LA Norwalk for 355 miles one way. I totally forgot to turn the TCS off and once we got to LA Norwalk and filled up the gas again at Costco which always has very long line waiting in California, I checked the AVG MPG info display which hasn’t been reset for a long time, 38.4, increased from 37.8 a bit at the Costco gas station in San Jose just before the trip.

On the way back yesterday I turned the TCS off the Yaris definitely behaves just like our CX-5, the car feels peppier which makes me believe the gas mileage should be improved. Wife drove the first part and I could hear the engine was roaring a lot in the mountain section on I-5 north of the LA. We stopped at the first rest area and I started to drive. I saw the AVG MPG showed only 36 which is worse than I expected. I immediately noticed the “SPROT” amber light was on in dash, and that’s why the engine revved very high in 4th or 5th gear even at 70+ mph! I turned the Sport mode and TCS off、reset the AVG MPG、and drove the next 200 miles. Even though there was a 40 minutes of stop-and-go traffic on I-5 due to a car accident, but when we stopped at the rest area and I checked the AVG MPG, I was shocked to see:

3DAF8346-8FC2-4636-9EE7-0F4C27E0D4E8.jpeg
4A5FEBFB-5D57-4F58-9BED-38B1C9209823.jpeg


We can see the “TCS OFF” icon is on in dash, but I’ve never seen such diesel like average MPG before, 49.2!

When we got to Costco gas station in San Jose after some mountain road driving on Hwy. 152, the Avg. MPG display still showed 46.0, and we drove 70~80 mph whenever possible, didn’t slow down trying to get better gas mileage.

The MPG calculation based on gas pump is 41.3 from SJ to LA with TCS on, 43.3 from LA to SJ with TCS off (but about driving with “Sport” mode on). I’m totally convinced turning the TCS off on Mazda vehicles somehow makes the engine peppier and more efficient (or less unnecessary braking by TCS), hence improves gas mileage significantly!
 
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Mazda CX-9 Signature
We need scientific data. Drive with the same people and cargo to Norwalk again tomorrow with TSC off and report back.

Lol jk. Could it be you were going mostly downhill since you've climbed in the earlier part of the driving?
 
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2016.5 CX-5 GT AWD titanium/black 2016 Miata Club ST MT white
Here's something that I don't understand about this.

It would seem that folks are getting better fuel economy with the TCS turned off. If this is really the case then why don't manufacturers turn TCS off when doing their fuel economy testing for the EPA? The number would certainly look better!

Does the EPA require TCS to be on during testing?
 

HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
Here's something that I don't understand about this.

It would seem that folks are getting better fuel economy with the TCS turned off. If this is really the case then why don't manufacturers turn TCS off when doing their fuel economy testing for the EPA? The number would certainly look better!

Does the EPA require TCS to be on during testing?
TCS became mandatory in 2012 with default to "on" at start up. It's a fair bet testing is done with TCS on. Testing is done on a dynamometer. If there's any gas savings in the real world it may not show up in that straight line testing that looks like this:


It is generally believed that TCS off saving on gas amounts to urban myth since theoretically it only engages when traction loss is detected. A particular implementation might be an exception, perhaps hypersensitive to minute slippages a driver does not detect with minute brake applications. If that's the case, worn tires might be one determining factor. In limited testing, I see no discernable difference in my CX-5.

I wouldn't assume that all vehicles of the same year / trim / drive train would perform the same. In the Japanese world of Deming continuous improvement, they could be tweaking software at any time even without a TSB if it is not a response to consumer complaints.
I think the liability would be too great if they let out the slightly hint to consumers to turn off any safety features
Clearly defaulting to off is a discouragement by regulation. But they let you do it. You're told to do it if you're stuck in snow, mud or sand. In point of fact, turning off TSC is easier than with any of the iACTIVESENSE features except lane keeping--just push a button, no drilling down through screen menus. They certainly "let on" you can turn stuff off. One just has to bothers to look. Maybe it is best that those who never bother should have them on since they don't know how their vehicle works. Then there's the question of whether an automaker believes this is urban myth as applies to their vehicles. And if you wreck with TCF off I would wager that fact is recorded in the black box.
Good point! People must be protected from themselves.
Well, people resisted seat belts when they were introduced. Then shoulder harnesses. People don't complain about the passive stuff that protects them from themselves (and others) or may have no clue how they work or that they are even there. Take air bags for example, never given a second thought unless they blow.

Or consider the geezer who says his 60's vintage 4,500 lb. boat's worth of Detroit iron was safer than the flimsy vehicles of today. He has no clue that antique vehicle was a death trap in comparison to modern vehicles with crumple zones and other passive protections.
 
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HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
During the Thanksgiving Holiday we drove our 2018 Toyota Yaris iA (Mazda2 in disguise) from San Jose to LA Norwalk for 355 miles one way. I totally forgot to turn the TCS off and once we got to LA Norwalk and filled up the gas again at Costco which always has very long line waiting in California, I checked the AVG MPG info display which hasn’t been reset for a long time, 38.4, increased from 37.8 a bit at the Costco gas station in San Jose just before the trip.

On the way back yesterday I turned the TCS off the Yaris definitely behaves just like our CX-5, the car feels peppier which makes me believe the gas mileage should be improved. Wife drove the first part and I could hear the engine was roaring a lot in the mountain section on I-5 north of the LA. We stopped at the first rest area and I started to drive. I saw the AVG MPG showed only 36 which is worse than I expected. I immediately noticed the “SPROT” amber light was on in dash, and that’s why the engine revved very high in 4th or 5th gear even at 70+ mph! I turned the Sport mode and TCS off、reset the AVG MPG、and drove the next 200 miles. Even though there was a 40 minutes of stop-and-go traffic on I-5 due to a car accident, but when we stopped at the rest area and I checked the AVG MPG, I was shocked to see:

View attachment 305063 View attachment 305062

We can see the “TCS OFF” icon is on in dash, but I’ve never seen such diesel like average MPG before, 49.2!

When we got to Costco gas station in San Jose after some mountain road driving on Hwy. 152, the Avg. MPG display still showed 46.0, and we drove 70~80 mph whenever possible, didn’t slow down trying to get better gas mileage.

The MPG calculation based on gas pump is 41.3 from SJ to LA with TCS on, 43.3 from LA to SJ with TCS off (but about driving with “Sport” mode on). I’m totally convinced turning the TCS off on Mazda vehicles somehow makes the engine peppier and more efficient (or less unnecessary braking by TCS), hence improves gas mileage significantly!
If I understand this correctly, you got MPG display readings of 49.2 and 46.0, much higher than your manual calculations. This goes to show how inaccurate the MPG displays happen to be, frequently reported by folks who do manual calculations.

My dash reading overstated the MPGs by 2.5 on my last tank when compared to a manual calculation. I could even see it coming--at half a tank with 200 miles on the trip meter the 28.8 displayed was an overstatement. Unlike you I get more accurate readings the more expressway miles are driven on a tank of gas.

So, your manual calculations show a 2.0 difference with some additional adjustment required for the 1/5 Sport mode miles. This could be accounted for by driving in different directions. A 15 mph headwind vs. tailwind alone could account for the 2.0 difference. Is one direction more uphill and the other more downhill for some additional incremental difference? I would not draw firm conclusions based on the facts presented.

In my tests I agree the vehicle seems somewhat peppier with TCF off--slightly less gas pedal pressure to get the same result. When adjusting for pedal pressure the vehicle performs the same in acceleration and shifting behavior. This would lead one to think that TCS is using less gas. On the other hand, these test were done on flat, smooth roads in a straight line with 12,000 miles on the tires, plenty of tread. It's hard to believe even a hypersensitive TCS is engaging. Though hard to believe, It could be TCS off adjusts throttle body behavior while still pushing the same amount of gas. With interconnected complexity of the various systems I wouldn't rule it out.
 
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Phoenix
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2021 signature
If you google acceleration (or gas mileage) with TCS off you'll find yourself going down quite the rabbit hole. From Mustang forums to Acura forums. I find 2-3 MPG difference hard to believe - 10% difference? Really? If there was a detectable difference I'd expect a bigger consensus than a split of 60%/40% in people "tests". An amalgam of all the posts would lead one to believe that if there is a difference, your butt and fuel calculations aren't going to detect it.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
If I understand this correctly, you got MPG display readings of 49.2 and 46.0, much higher than your manual calculations. This goes to show how inaccurate the MPG displays happen to be, frequently reported by folks who do manual calculations.

My dash reading overstated the MPGs by 2.5 on my last tank when compared to a manual calculation. I could even see it coming--at half a tank with 200 miles on the trip meter the 28.8 displayed was an overstatement. Unlike you I get more accurate readings the more expressway miles are driven on a tank of gas.

So, your manual calculations show a 2.0 difference with some additional adjustment required for the 1/5 Sport mode miles. This could be accounted for by driving in different directions. A 15 mph headwind vs. tailwind alone could account for the 2.0 difference. Is one direction more uphill and the other more downhill for some additional incremental difference? I would not draw firm conclusions based on the facts presented.

In my tests I agree the vehicle seems somewhat peppier with TCF off--slightly less gas pedal pressure to get the same result. When adjusting for pedal pressure the vehicle performs the same in acceleration and shifting behavior. This would lead one to think that TCS is using less gas. On the other hand, these test were done on flat, smooth roads in a straight line with 12,000 miles on the tires, plenty of tread. It's hard to believe even a hypersensitive TCS is engaging. Though hard to believe, It could be TCS off adjusts throttle body behavior while still pushing the same amount of gas. With interconnected complexity of the various systems I wouldn't rule it out.
Actually the difference between computer calculation and gas station manual calculation is very minimum from my CX-5 and Yaris iA. The overall manual calculation on both trips, 41.3 from SJ to LA with TCS on, 43.3 from LA to SJ with TCS off, is still significant to me as the first 80 miles with Sport mode on which resulted 36 mpg does impacted the gas mileage from LA to SJ otherwise I’d imagine the manual calculation could be at least 2~3 better than 43.3.

When we’re dealing with 40 mpg range, every minor thing could affect the mpg greatly.
 
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2018 CX-5 Sport
I think the traction control system is broken in some of these cars and for some reason TCS drags the brakes when it is on. I would want you guys to check the brake temperature after a drive with TCS on and TCS off to see if the brakes are hotter with it on than with it off. I have no difference in mpg or pep when my TCS is off. Has anyone else tested their car?
 
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2017 Mazda 6 Sport
I think the traction control system is broken in some of these cars and for some reason TCS drags the brakes when it is on. I would want you guys to check the brake temperature after a drive with TCS on and TCS off to see if the brakes are hotter with it on than with it off. I have no difference in mpg or pep when my TCS is off. Has anyone else tested their car?
It feels more like engine torque than brakes being applied
 

HardRightEdg

US 2020 CX-5 Touring AWD Soul Red
Actually the difference between computer calculation and gas station manual calculation is very minimum from my CX-5 and Yaris iA. The overall manual calculation on both trips, 41.3 from SJ to LA with TCS on, 43.3 from LA to SJ with TCS off, is still significant to me as the first 80 miles with Sport mode on which resulted 36 mpg does impacted the gas mileage from LA to SJ otherwise I’d imagine the manual calculation could be at least 2~3 better than 43.3.

When we’re dealing with 40 mpg range, every minor thing could affect the mpg greatly.
I fail to understand. You posted MPG display readings that are far above your manual calculations. I don't see how you can call the discrepancy minimal.

"Every minor thing could affect mpg greatly."

My point exactly, with a couple of possible factors noted.
 

yrwei52

2016 Mazda CX-5 GT AWD w/Tech Pkg
Contributor
:
Plano, Texas, USA
I fail to understand. You posted MPG display readings that are far above your manual calculations. I don't see how you can call the discrepancy minimal.

"Every minor thing could affect mpg greatly."

My point exactly, with a couple of possible factors noted.
Read my post. I reset the computer AVG MPG calculation once after driving the first 80 miles with Sport mode on the way back to San Jose. Since the rest 275 miles was without Sport mode, hence the computer MPG calculation after the reset got higher. The manual calculation is for the entire 355-mile trip, with and without Sport mode.