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Do Brake lights come on when Cruise Control slows car?

On more than one occaision it appears that the brake lights don't come on automatically when cruise control slows car. Noticed following cars panicing when our car is rapidly slowed by the collision avoidance/cruise control system. Dealer says it does but really no way to be sure when driving. What say you?
 
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I’m sure they do. Mazda would not have the car brake automatically without lights.
 
"On more than one occaision it appears that the brake lights don't come on automatically when cruise control slows car."
When you say "it appears"...how you you know? Did someone tell you or shake their fist? Never had an issue.
 
"On more than one occaision it appears that the brake lights don't come on automatically when cruise control slows car."
When you say "it appears"...how you you know? Did someone tell you or shake their fist? Never had an issue.
The brake screeches and lip reading say it all. Short of having someone follow and report it make me nervous. I do know when the giant red "BRAKE!!!" symbol fills the HUD my foot is on the brakes and lights are on. Could be tailgaters as well. Not sure dealer knows for sure so disconcerting.
 
Not sure i understand your issue exactly. The cruise control is suppose to slow you down fairly slowly, without the big red brake warning light, unless traffic in front of you stopped really abruptly. What year is your CX-9? Earlier CX-9 where known to have their emergency braking system a bit too nervous, but it still shouldn't engage regularly when using cruise control.

Basically, radar cruise control is supposed to slow you down progressively, emergency braking system/avoidance collision system is to prevent accidents and brakes really hard. It shouldn't be relied on for as a cruise control substitute. Is the situation you are experiencing when using cruise control or when the emergency braking system comes on ? (big red BRAKE!! symbol)
 
2016. Nervous braking is a good description. Most noticable is when cruise brakes suddendly and next guy is follwing too close. Sometmes i wonder if car behind me has radar as well and set to min distance.
 
when that happens do you have radar cruise control engaged or off and do you get the red flashing Brake! warning ?

If you want you can go in the settings to change how early the emergency braking system engages. Setting it at low may reduce unwanted nervous braking (assuming it is braking too early for your likings) and would not change the distance at which cruise control slow downs.
 

Ronzuki

South Central PA
:
2018 CX5 Touring
:
w/ Pref Pkg
Not sure i understand your issue exactly. The cruise control is suppose to slow you down fairly slowly, without the big red brake warning light, unless traffic in front of you stopped really abruptly. What year is your CX-9? Earlier CX-9 where known to have their emergency braking system a bit too nervous, but it still shouldn't engage regularly when using cruise control.

Basically, radar cruise control is supposed to slow you down progressively, emergency braking system/avoidance collision system is to prevent accidents and brakes really hard. It shouldn't be relied on for as a cruise control substitute. Is the situation you are experiencing when using cruise control or when the emergency braking system comes on ? (big red BRAKE!! symbol)
:ROFLMAO: Seriously? "Supposed to"?:ROFLMAO: Where does it say what any of this junk is "supposed" to do? :ROFLMAO: ...more problems resulting from half-assed automotive automation. 'Supposed' to slow you down gradually...great idea in concept and theory, until, another vehicle cuts you off diving into your radar's 2-3 vehicle distance gap at 70mph. A simple thing like turning on the brake lights when the brakes are applied is a pretty basic automation concept and an epic design miss/fail right there if proven they do not illuminate. But as I've preached elsewhere on this forum, as well as others, the current crop of automotive automation idiots have a lot to learn.

There are far too many circumstances that would dictate the rate at which a vehicle on unpredictable non-standard public roads would need to stop. I've programmed AGVs on closed circuit courses and even at that, the challenges and what-ifs are numerous and must all be accounted for in order to obtain both safe and reliable operation. Try thinking about if you were the guy programming the braking system, in a car, on roads, in all types of conditions that you have zero control over and can't predict This is assuming of course the proper sensing hardware was in place to provide the critical feedback required to do so (which the crap in these cars is absolutely not). Think about this while you are actually driving, one simple trip and how you would deal with each and every situation that required your foot to work the pedal and how quickly and forcefully it worked the pedal. COUNTLESS scenarios requiring a crap-ton of exception handling programming (again, assuming the correct hardware is in place, which isn't because there's not enough money on the planet). Since I've turned all of this half-baked crap off in my CX5, I no longer have the thing incessantly beeping at me for no good reason, and most importantly, have not nearly been rear-ended at all because of illogical, sudden high-rate slow downs or stops. I do use the RACC quite often but I am fully aware of its limitations...ie, I assume it can not stop me when it needs to and/or that it will slow me suddenly and too rapidly, or stop me completely, when it really shouldn't.

Consumers have to stop believing the technology in these cars is flawless...it's a far cry from it. In my world this stuff is barely prototype level and it certainly would not be deployed for mainstream utilization. What it is...is marketing gimmics. Merely listen to any automotive TV commercial. Tech tech tech...tell them what they want to here...build it, and they will come!
 
When I said, supposed to, I meant in normal operation of a functional system, as a baseline to compare the behaviors he is experiencing in an attempt to determine its root cause. The taillights do turn on when using radar cruise control. This has been discussed nunerous time on this forum, especially with regards to trailer wiring.

Just like you I regularly use radar cruise control and even let it brake for me (with foot close to the brake pedal in case of malfunction) and never have an issue with people rear ending me so I am trying to figure out the details of his concerns.

I don’t disagree with you about the limitations of all these autonomous systems.
 
The cruise control is so good i wish i could adapt it to all my other cars. Like said before its addictive and you have to remind yourself what you are driving and what features are available. Based on discussion with couple,agents I think its just a matter of time before insurance companies drive up rates for old cars without all the safety and collision avoidance gizmos. GPS locators too.
 
:
North of Toronto
:
2019 CX-9 Sig
I believe I had read Car and Driver early review of this gen saying the emerg braking and ACC was sensitive. i'd need to dig for article...

But subsequent reviews don't seem to mention, and it behaves seemingly with appropriate sensitivity on my 2019.
 
You are correct. It was one of the reason the 2016 didn’t win their car of the year award. The system has been retuned for the 2018 model year and up ( it was one of the few unadvertised changes for 2018). I have no issues with mine on my 2018 GT.
 
when that happens do you have radar cruise control engaged or off and do you get the red flashing Brake! warning ?

If you want you can go in the settings to change how early the emergency braking system engages. Setting it at low may reduce unwanted nervous braking (assuming it is braking too early for your likings) and would not change the distance at which cruise control slow downs.
I changed the setting to "near" and the "auto braking" in cruise is now much less jarring. Thanks for the tip as my dealer was clueless, seems many of the features are unknown to them and this is a Mazda only dealership. Still not sure the brake lights come on when "auto braking" but it just seems better since the change. Maybe a small braking indicator light on the dash would be an idea,
 
:
2010 CX-9 GT
The cruise control is so good i wish i could adapt it to all my other cars. Like said before its addictive and you have to remind yourself what you are driving and what features are available. Based on discussion with couple,agents I think its just a matter of time before insurance companies drive up rates for old cars without all the safety and collision avoidance gizmos. GPS locators too.
Heh. Read this:

Turns out that all the new tech is actually driving rates higher. The money the insurance companies saved due to the new safety systems reducing accidents has been more than offset by increased repair costs when a car is damaged.
 

Ronzuki

South Central PA
:
2018 CX5 Touring
:
w/ Pref Pkg
Gee...there's a real shocker....and who gets to eat the increased costs? Certainly not the insurance companies.

Combined w/ : https://www.leaseguide.com/articles/disturbing-new-car-cost-trends/

"Some new safety technology is not fully tested and subject to recalls. Many features of expensive “infotainment” systems are of little or no use to many drivers, although they make for exciting advertising."

Again...shocking...
 
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:
2010 CX-9 GT
I think the biggest issue right now is that there is no standardization across manufacturers for the various sensors and other components that make up these systems. That's why Mazda can charge $600 for a blind spot sensor or >$2000 for the radar module in the middle of the grille - you have no other choice.

Personally, I'd still rather have the systems - I'll trade a few hundred bucks for a reduced risk of a collision.

Eventually, one has to hope, these parts become standardized and third parties and the OEM manufacturers can start selling replacement parts.
 

sm1ke

Work In Progress..
Moderator
Contributor
:
Canada
:
'18 CX-9 Signature
You are correct. It was one of the reason the 2016 didn’t win their car of the year award. The system has been retuned for the 2018 model year and up ( it was one of the few unadvertised changes for 2018). I have no issues with mine on my 2018 GT.
Interesting, I had no idea. Do you have a source for this?
 

Ronzuki

South Central PA
:
2018 CX5 Touring
:
w/ Pref Pkg
Eventually, one has to hope, these parts become standardized and third parties and the OEM manufacturers can start selling replacement parts.
One can hope for a lot of things ...standardization of the actual parts themselves...across multiple manufacturers...never going to happen. Hasn't for proprietary industrial components across different manufacturers, ever, and likely won't in automotive either. They may share some of the root tech, but exact form, fit, and function?...never. Same manufacturer, across their own models, certainly plausible.

Aftermarket (3rd party) may step up, but that's a risky proposition regarding anything attached to the over-used "safety" mantra. The added costs to parts implemented in safety systems are stupid high. 3rd party or not.
Question: if one is truly concerned about having all of this high-tech safety non-sense in a car, which would you rather have, looking at things from a purely 'safety-first' perspective...a reverse engineered 3rd party knock-off made in the dankest corners of the globe, or, the real factory engineered and supposedly-tested parts? C'mon now, let's not get all cheap here...when it's all about safety.
 
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Interesting, I had no idea. Do you have a source for this?

having a hard time digging it up. It was motortrend instead of car and driver. The first link above mentions it briefly at the end but the second one goes into more detail. Here is a copy paste of the relevant section since the 2nd article is a longer read. The system tuning change as been documented on various 2018 reviews.

« This is where we learned, for example, that the Mazda CX-9 is more on-edge than a driving instructor after 12 venti lattes. Slowing gradually for a stopped car in front, the Mazda suddenly applied full braking, mistakenly thinking it was helping to avoid a crash when in actuality it nearly caused one. At one point, I was in the Mercedes GLC and following one of the CX-9s when the Mazda screeched to a stop. Minus one point for the Mazda, plus one for the Mercedes and its quick-responding brakes, and score one for Priddle in the Mazda, who picked up her CB radio and taught me how to curse with a beautiful Ontarian accent. »
 
:
2010 CX-9 GT
One can hope for a lot of things ...standardization of the actual parts themselves...across multiple manufacturers...never going to happen. Hasn't for proprietary industrial components across different manufacturers, ever, and likely won't in automotive either. They may share some of the root tech, but exact form, fit, and function?...never. Same manufacturer, across their own models, certainly plausible.

Aftermarket (3rd party) may step up, but that's a risky proposition regarding anything attached to the over-used "safety" mantra. The added costs to parts implemented in safety systems are stupid high. 3rd party or not.
Question: if one is truly concerned about having all of this high-tech safety non-sense in a car, which would you rather have, looking at things from a purely 'safety-first' perspective...a reverse engineered 3rd party knock-off made in the dankest corners of the globe, or, the real factory engineered and supposedly-tested parts? C'mon now, let's not get all cheap here...when it's all about safety.
I think you are misrepresenting the situation. Standardization of car parts is already happening - go look at how many cars use ZF or Aisin transmissions, Bosch or Denso fuel injection, etc. These days, most of the auto manufacturers rely on other companies for parts as well as entire subsystems rather than design things themselves. You can go on RockAuto and they will often times tell you who actually makes the OEM parts. In those instances you can buy the "real factory engineered and tested parts" directly from the original manufacturer and not have to pay the absurd markup the car companies apply to "OEM" parts.

Eventually, there will be some level of commonality in these systems much like everything else - how much is a valid question. I would hope that things like parking sensors and blind spot sensors would trend in this direction as they are installed on more vehicles. Other parts may never get there, depending on the complexity. I could also see the IIHS actually get involved and start naming and shaming the manufacturers over this issue, much like they already do for crash testing, headlight quality, etc...
 
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