Mazda Radar Cruise Control

14M6GT

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2014 Mazda 6 Grand Touring
I found something about the 2014 M6 that I do not like. The MRCC is annoying and potentially dangerous. When driving on the highway, if a car changes lanes in front of you fairly close with the MRCC on, either 1.) the throttle closes, or 2.) the trans downshifts - even if there is no need to do this. That's extra wear and tear, and hurts fuel economy as you accelerate back to programmed speed. With conventional cruise control, you just touch the cancel button if it seems too close.

Last week, while driving on Route 80 westbound with light traffic at 65MPH, in a spot where the highway twists to the left, a tractor trailer was ahead slightly in the right lane. The MRCC picked up the truck and applied the brakes hard - causing traffic behind me to do the same. Luckily there were few cars and all followed at safe distance.

On a country road at a steady 50 MPH, if there is a slight down hill, the MRCC will downshift to hold the programmed speed instead of coasting and taking advantage of gravity and momentum. More wear on the trans. So what if it goes from 50 to 52 MPH?

An expensive and unnecessary "improvement" over conventional cruise control. In all fairness, I can see how non-car people would think this is great.

Other than that, this is an excellent automobile so far.
 
Yup, as soon as I see the freeway curving too much and that I have cars in the next lane, I just hit the cancel/off button. It's insanely dangerous and I expect trouble for Mazda and anyone using it without being careful/aware.

With that said, I actually really like the MRCC system and I'm hoping Mazda can provide a future update to fine tune it a little better. One thing I've learned about the new Mazda6 is that while it's geared towards driving enthusiasts (better handling / road feel) it is so packed with convenience features like MRCC that it is slowly turning me into a lazy driver. The good news is my gas mileage actually improves since I'm becoming less of a lead-foot, and more of a commuter... There's always the weekends and road trips though and that's another kind of driving.
 
As with any system, you need to understand it capabilities and limitations before you can properly use it. Expecting it to work flawlessly in ANY situation and driving accordingly is indeed dangerous.

I for one really enjoy using it.
 
Try getting used to the MRCC and then driving a loaner CX-5 that has cruise but not the adaptive kind... I wont say I nearly ran into a car, but for a second, I was wondering why my CX-5 wasnt slowing down as I got closer... DUH! No MRCC. It's very dangerous taking new technology for granted... Be careful out there folks. Use your noggin to save your noggin, and other noggins too.
 
The manual explains in great detail that curved roads will affect the system. I don't use this often since I commute during rush hour, but it works great. Has anyone tried disabling MRCC, do you still have the traditional cruise control functionality?
 
i also have mdcc on mine i wonder if it would act better if you go into programming and shorted the distance before it kicks in.
 
i also have mdcc on mine i wonder if it would act better if you go into programming and shorted the distance before it kicks in.

Huh? You can shorten the distance right there on your steering, via one press of one button
 
We got the MRCC sort of thrown in on the deal and did not investigate it thoroughly before hand. We REALLY dislike the feature and find it extremely dangerous on the highway, slamming on the brakes at 75 mph when we are passing a semi...... would love to have it turned off and 'normal cruise control" restored. Has anyone heard of how to do this?
 
Bringing up an old thread. Had the new car 3 weeks, really hate the MRCC, is there a way to disable it and just have cruise. So many situations where it is dangerous!

Driving on a STRAIGHT autobahn, doing 90mph, passing some trucks and the brakes slam on, luckily nobody behind. This happens too often now, I just leave it off.

The problem is, the MRCC can not see the road situation ahead, it just reacts to the car infront, so if the guy in front has a heavy brake foot, then your car drives the same way, making you look like a idiot on the road too. Normally with cruise on, I see a truck pulling out to overtake and there are a few cars having to slow up behine it, I would cancel cruise, coast up slowly, follow the truck, then as it pulls in press resume, with MRCC, it applies the brakes quite suddenly, if you are slowing from 100mph to 55mph, MRCC has to put the brakes on very hard, for me MRCC has applied the brakes in an autobahn more in the last week than I have done myself in the last year. This system isn't build for German autobahns!

Also, if you are in the slow lane, you see a slow vehicle coming up but you need to let someone faster than you past, once the faster vehicle passes and you pull out, if you get a little too close (but still safe distance) to the vehicle you are going to overtake, the MRCC goes crazy and slams on the brakes.

Last complaint, once you are sitting behind a slow vehicle, the distance even on the shortest setting, is quite far, people cut out infront, and again, instead of coasting back a little, the brakes get applied.

My wife was shocked coming back on the Autobahn today, she never uses cruise, and this experience means she would never be persuaded to use it.
 
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Dr Watson - the MRCC works fine for non-aggressive driving. If you intend to drive aggresively and pass you need to disable it and use your foot and head. MRCC is beautiful when you want to lope along at a set speed behind traffic without ever getting too close. It's also handy to know someone in front of you might be going slower so you can change lanes far sooner and then pass them. Lastly if you gun the vehicle it does disengage until you let off the throttle to coast and unlike Audi/BMW it will not slam on the brakes to bring you back down to the set cruise speed, but it lets you calmly coast back to speed. These things do take a LOT of getting used to, but if you drive calmly and sanely and not try to pass everyone and everything it can be a really nice relaxing feature. That said, I do wish I could occasionally disable it and turn it into regular old dumb-cruise control sometimes.
 
Sorry, you are presuming too many things. My MRCC does not work very well in many conditions and my driving style is certainly not to blame, far from it, I am a very alert driver, giving a lot of space to other vehicles.

The MRCC brakes my vehicle as I pass by a Semi, sometimes it slows the car to the same speed as the Semi until I am driving along next to it, in the outside lane, with a car coming up behind me doing 3 times my speed, this is very dangerous.

Maybe the speeds I mentioned make it sound aggressive, but these roads have no speed limit (Germany), the left lane is used for passing, with most vehicles doing 100+ in that lane. So far I have found that the US version of the CX5 and possibly the 6, can disable the MRCC and keep cruise on. The procedure is in the smart start guide.

However, the EU version does not have a seperate Cruise/MRCC ON and OFF button, it has a single toggle button that does not disable the MRCC.

The list of conditions when MRCC should be be used is pretty extensive, so I would expect an option in the EU model to use cruise only.

* MRCC may not perform as expected due to factors such as the shape of the vehicle in front (some shapes do not reflect radar well, etc.), bad weather (rain, snow, fog, etc.), and road conditions (multiple curves, undulations, etc.).

The smart city guide even comments on my own experience!

NOTE: The MRCC sometimes will brake your vehicle when passing a very large
vehicle such as semi truck (tractor trailer) due to the sensitivity of the front sensor
system. This is normal. Simply press the accelerator pedal to override the system
and maintain your desired speed.


Switching to conventional cruise control function:
When the ON switch is pushed continuously for about 2 seconds while the
Mazda Radar Cruise Control (MRCC) system is turned on, the system is
switched to conventional cruise control function.
The Mazda Radar Cruise Control (MRCC) indicator light (green) in the
instrument cluster turns off and “Radar Cruise Control deactivated”
message is displayed in the multi information display at the same time.
 
It sounds like the Mazda radar cruise has the same issues I have seen over the years with my '07 G35x. Once I get in heavy traffic I either don't use or override to old school manual cruise control and tweak as needed.

The funnest cruise control I have ever used was in a Q50. It followed the speed limits and did a pretty good job of basically driving itself as the lane guidance worked the steering wheel as well.

Does the Mazda radar cruise change the speed at all in the turns? The Intelligent Cruise (ICC) in my Infiniti tries to take corners at lower speeds and then speeds back up to presets on the straightaways


 
I got a call from my dealer today. They have found an issue and should have a computer fix for this adaptive cruise control issue next to trucks. Supposedly only happens after the car has been driven quite a few miles. I will be calling my new dealer Ina few weeks to get it fixed.
 
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