Haven't had any luck with dealer service department yet (though they are trying), hoping someone here has some ideas:

Purchased new 2016 CX-5 GT AWD w/i-ACTIVESENSE at the end of March, and within a week started receiving the following two error messages on my info panel:
"Smart City Brake Support Malfunction. Forward SCBS Disabled." and
"Smart Brake System Malfunction"

Both messages show up in tandem, never just one or the other, and at seemingly random times. Once I turn the car off, they disappear and then pop up again after a few days or weeks. The dealer asked several questions about weather conditions, time of day, highway vs. city, windshield sensor debris/fog, etc. But the messages have appeared in just about every combination of driving conditions. Dealer kept the car for a couple days, could not recreate the issue or find anyone else with this issue, eventually Mazda told them to replace some ABS part...two days later, message appeared again.

Dealer keeps telling me they need to run diagnostics while the messages are on the screen but given the randomness of the problem, neither I nor they have been able to recreate on demand. Closest thing to a pattern I've recorded is that the error is more likely to set off when driving at slow speed and/or slowly applying the brake; the car usually jerks a bit (which i assume is the SCBS kicking in briefly?) and then the messages appear. For example, once they appeared while in the middle of a U-turn after I was stopped at a red light.

Thanks for your help and suggestions!

 

Having the same issue, although mine came on when starting the car. At the dealer now; left the car running when I arrived so they could see the warning messages. Also had the tire pressure warning light come on at the same time. Will post what they find. There was a software update installed a week or so ago, so now sure if the malfunction might have something to do with the software update...

 

The service manager was glad that I'd left the car running when, as he was (a) able to see the warning lights on the dash, and (b) was able to run the diagnostics with the car running.

What set off the SCBS malfunction was a malfunction in the tire pressure warning system. There was nothing wrong with the pressures themselves, but the TP warning tripped for some unknown reason, which triggered the SCBS malfunction and disabled the forward SCBS. He reset the tire pressure system, cleaned out the codes and all the lights went back to normal.

He said that if there is an EZpass (toll transponder) located in the upper right corner of where all the lasers/computers/cameras are, the transponder "might" be interfering with the SCBS. There is another SCBS device in the Mazda logo in the front grill; if that gets dirty or something is covering the Mazda logo, that "might" trigger the SCBS to malfunction.

Basically, he didn't know what was going on and hopes it was just the tire pressure issue which dumped the SCBS. He was interested that someone else had had the same problem.

 

BIG THANKS Parclark! I just got back from the dealer and had to leave my CX-5 with them again because they did not have a solution and we could not recreate the warning lights today (they kept the car for a few days in April as well but had no luck). I even had an in-person meeting with a Mazda Corporate rep explaining that if the problem continues we will have to start the process of exchanging my car for a new CX-5. I'll forward the information you provided to my dealer service manager and let you know what they say.

In case your dealer wants to talk with mine:
C.J. Wilson Mazda of Countryside
6060 South La Grange Road, Countryside, IL 60525
(708) 354-2700

Now if only they could fix my fuel economy issue: averaging only 20.8 mpg after 2,100 miles with 70% highway driving (and not aggressive accel/braking, etc)!!

 

Try resetting your MPG info (press the center of the info button down on the steering wheel). Unlike other cars, it doesn't automatically reset when you fill up or reset the trip odometer. I was getting really low average MPG readings until I reset the info after filling up (took me a while to figure out how to do it, but it is in the manual). I've gone 11000 since March and am getting between 27-29 MPG combined city/highway, and have been getting about 28-30 straight highway (I try to maintain a steady 70...). The MPG improved, dramatically, after the first oil change at 5000, despite Mazda saying there is no break in period; before the first oil change the average MPG was down around 23-26. My dealer asked how the mileage was when I was there getting an oil change in my husband's Mazda3, and she said to wait until after the first oil change, and I'd see a big difference.\

And if the SCBS warning happens while you are driving the car, don't turn off the car and take it to the dealer, and leave it running...

 

Thanks again, will try resetting. Just had first oil change today, though only 2,100 miles (dealer strongly suggested anyway since I've had the car for 5 months...free, so I didn't argue much). One service manager said MPG doesn't settle until 10,000 miles!

 

Latest update in case anyone else has this problem: I left my CX-5 with the dealer on 9/2. They ran tests, drove the car for over 100 miles until they recreated the malfunction lights I was having, then determined that the Smart City Brake Support sensor needed to be replaced, which they did. They also said they needed to remove the 3rd party remote starter (that they originally recommended/installed when I purchased the car), which has a receiver/antenna on the upper windshield near the sensors, and replace it with the Mazda OEM remote starter. They returned the car to me on 9/14 in the afternoon. After 5mins of driving during the morning of 9/15, the car jerked and the same malfunction lights turned on again! This time, I was able to leave it running and drive straight to the dealership, not that it should have mattered since they already recreated the problem. Service manager said Mazda told him to re-run the same diagnostics again (why?!), and of course the test results were the same as before. Had another long wait and eventually we called the District Service Manager to re-iterate my request to have this lemon replaced with a new, properly functioning car. Obviously she would not commit to that, though after 6 months of this I think it's a very reasonable request. So I left the car with them yet again.

9/17: just got a call from a service rep...now they are going to replace three more parts: "rear body control module, radar sensor, sas control module". This is in addition to the SCBS sensor earlier this month and some ABS part the first time I left the car with them in April. Maybe I'll get the car back next week, maybe it will work.

My wife's suggestion: "Just ask if they'll take this car back and give you a Honda CR-V instead"...maybe she's right

 

9/25: picked up my CX-5, service manager answered all my questions and they showed me the SCBS in action to ensure it was working.

9/28: driving down the highway, car jerks and the same malfunction warnings turned on again! Unfortunately, the diagnostics and repairs over the past 6 months did not work (note: I edited my previous posts, as I forgot to mention that they also removed the 3rd party remote starter that they originally recommended/installed and replaced it with Mazda OEM remote...so 6 replacement parts in total so far).

The saga continues, will let you know the final resolution (which at this point better be a new CX-5...or maybe they'll pony up and get me a Volvo XC-60 ).

 

I don't know about Illinois but in Texas you have met all of the requirements to invoke the lemon law. Good Luck

 

I quickly looked into IL Lemon Law thanks to suggestions from forum users. I think here it's 4 repair attempts or 30 days out of commission...so I'm close. But I've been talking to Mazda corporate customer service for weeks now and they seem to be taking this seriously, so hopefully they'll come thru. I'll let everyone know how they resolve the issue.