I purchased a new mazda cx-9 in sept 2017 because it had the highly touted smart city braking system for which i paid thousands extra. i had had a previous rear end collision and wanted to be sure this system would at least warn me. i set up some cardboard boxes wrapped in aluminum foil. i slowly (10 mph) drove the car into them without touching the brake or accelerator. the car did not slow down or warn me.(i tried sending a video to you from my iphone which may not go through) i made an appoint to repair this obvious factory defect and significant safety issue. the service manager at olympia lincoln /mazda(and puyallup milam mazda) refused to repair it they stated and showed me a print out from mazda factory that forbids real time testing and stated that if the trouble light is not on they aren't allowed to repair or real time test it. i think that the factory is afraid of dealing with a massive safety recall. to compound things the active live traffic display doesn't work either which makes matters worse since i can't see where an accident has occurs in real time. i understand its defective in most mazdas with navigation in 2016 and beyond. the is a class action law suit starting to be filed about this. *bf consumer stated regarding defective automatic braking system on 2018 mazda cx-9. i have not heard back after filing this complaint 2 months ago. updated 8/24/18*jb