What 170 owners told NHTSA about the 2011 Mazda Cx-90 Phev

BRAKE PEDDLE STIFF, MAKES HISSING NOISE. AT TIMES WHILE IN TRAFFIC LOSS OF BRAKING ABILITY HAPPENS.

NHTSA ODI 11115730

CURRENT MILEAGE: 125707. NOTED BRAKE FADE, INSUFFICIENT BRAKING RESPONSE DURING NORMAL CITY DRIVING. THE VEHICLE WAS TOWED TO A LOCATION TO HAVE THE BRAKES EXAMINED. NEW FRONT ROTORS, CALIPERS AND BRAKE PADS WERE INSTALLED. BRAKE SYSTEM BLED AND VEHICLE TEST DRIVEN. NORMAL BRAKING DURING SPEED TESTS OF CITY DRIVING AND EMERGENCY BRAKING. VEHICLE THEN DRIVEN FOR 2-3 DAYS OF NORMAL OPERATION. OPERATOR DRIVING THE VEHICLE AND WHEN BRAKING TO A STOP ON APPROACH TO AN INTERSECTION NOTED THE BRAKE PEDAL WENT TO THE FLOOR BEFORE VEHICLE WOULD SLOW. THE PEDAL HAD TO BE PUMPED TO OBTAIN A MEASURE OF BRAKE RESPONSE. THE VEHICLE TOOK LONGER TO SLOW TO A STOP. ALSO NOTED DURING BRAKING WAS A "HISSING" NOISE WHEN DEPRESSING THE PEDAL. PEDAL WAS THEN PUMPED UP ON APPROACH TO ANY ANTICIPATED STOPPING POINT. VEHICLE TAKEN TO BE CHECKED FOR POSSIBLE AIR IN THE BRAKE LINES. BRAKE SYSTEM CHECKED FOR AIR IN THE BRAKE LINES AND NONE FOUND. TAKEN TO A THIRD-PARTY SHOP FOR ANALYSIS. IT WAS DETERMINED THAT THE MAZDA OEM POWER BRAKE BOOSTER HAD FAILED AND PER THE MECHANIC (NOTE ATTACHED PDF) THE DIAPHRAGM HAD BECOME "BRITTLE" AND THE BRAKE POWER BOOSTER FAILURE CAUSED THE "HISSING" NOISES AND THE BRAKES TO BE CAUSING THE BRAKES TO BECOME UNRESPONSIVE. THE OEM BRAKE BOOSTER HAD TO BE REPLACED. DURING A REVIEW OF ONLINE INFORMATION IT WAS DISCOVERED THAT THE NHTSA HAD CONDUCTED AN INVESTIGATION INTO THE ISSUE OF MASTER BRAKE CYLINDER LEAKAGE REGARDING THIS GENERATION OF MAZDA BRAKE BOOSTERS. THE VEHICLE HAS BEEN IN TO A MAZDA DEALERSHIP FOR PRIOR RECALL REPLACEMENT OF OTHER DEFECTS, HOWEVER THIS POTENTIAL DEFECT WAS NOT ADDRESSED.

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THE BRAKE START LOSING POWER AND NEED TO PUSH REALLY HARD TO STOP.. AND ALSO MAKE LOSING AIR SOUND WHEN PUSH ON BRAKE

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MY BRAKES DID NOT RESPOND AS THEY NORMALLY WOULD UPON APPLICATION OF THE BRAKE PEDAL WHEN APPROACHING AN INTERSECTION ON THURSDAY MORNING. IT FELT ALMOST LIKE THERE WAS A PILLOW UNDER THE BRAKE PEDAL. THIS OCCURRED ONCE ON THURSDAY MORNING, AND ONCE ON FRIDAY AFTERNOON. FRIDAY EVENING BRAKE FLUID WAS FILLED TO ENSURE THAT THERE WAS NOT A LACK OF FLUID CAUSING THE PROBLEM, HOWEVER THE PROBLEM AGAIN OCCURRED SEVERAL TIMES ON FRIDAY EVENING AFTER ADDING BRAKE FLUID. BY SATURDAY MORNING IT WAS WORSENING BOTH IN FREQUENCY (OCCURRING WITH EVERY APPLICATION OF THE BRAKE) AND SEVERITY (FELT AS THOUGH NO MATTER HOW LONG AND HARD I APPLIED PRESSURE TO THE BRAKES IT WOULD NOT PERFORM IN A MANNER THAT WOULD BE EFFECTIVE IN ANYTHING OTHER THAN VERY SLOW SPEEDS WITH EXCESSIVE SPACE BETWEEN ALL VEHICLES). ON SATURDAY IT ALSO BEGAN MAKING A HISSING NOISE WHICH OCCURRED AS I WAS DEPRESSING THE BRAKE PEDAL, THEN STOPPED WHEN THE BRAKE PEDAL WAS FINALLY FULLY DEPRESSED (WHICH TOOK AN EXTRAORDINARILY LONG TIME). I FELT IT WAS NO LONGER SAFE TO DRIVE OTHER THAN TO GET IT TO OUR MECHANIC WHICH I DID ON MONDAY MORNING. OUR MECHANIC TESTED IT AND DETERMINED THAT THE BRAKE VACUUM BOOSTER HAD FAILED AND HAD TO BE REPLACED.

NHTSA ODI 11104600

NOTICE WHILE ON LINE FOR GAS, MAINTAINING FOOT ON BRAKE PEDAL CAR BEGAN TO MOVE FORWARD AND HAD TO APPLY MORE FOOT PRESSURE. CAR HAS 690000 MILES AND OVER 7 YEARS OLD. IN PARK WHILE DEPRESSING THE BRAKE PEDAL CAN HEAR A HISSING SOUND. SYMPTOMS GETTING WORST, BRAKING DISTANCES ARE LONGER AND TAKES MORE PEDAL PRESSURE.

NHTSA ODI 11101868

TL* THE CONTACT OWNS A 2011 MAZDA CX-9. WHILE DRIVING AT AN UNKNOWN SPEED, THE BRAKES FAILED TO RESPOND WHEN THE BRAKE PEDAL WAS DEPRESSED. THERE WERE NO WARNING INDICATORS ILLUMINATED DURING THE FAILURE. THE DEALER WAS NOT CONTACTED. THE VEHICLE WAS TAKEN TO AN INDEPENDENT MECHANIC WHERE IT WAS DIAGNOSED THAT THE BRAKE BOOSTER FAILED. THE VEHICLE WAS REPAIRED. THE MANUFACTURER WAS NOTIFIED OF THE FAILURE. THE VIN WAS UNKNOWN. THE FAILURE MILEAGE WAS 120,000.

NHTSA ODI 11096513

TL* THE CONTACT OWNS A 2011 MAZDA CX-9. WHILE DRIVING 40 MPH, THE BRAKE PEDAL WAS DEPRESSED, BUT WAS EXTREMELY FIRM. THE CONTACT STATED THAT GRADUALLY THE BRAKE PEDAL TRAVELED TO THE FLOORBOARD BEFORE THE VEHICLE WAS ABLE TO BE STOPPED. THE VEHICLE WAS TAKEN TO CARDINALEWAY MAZDA-PEORIA (8424 W BELL RD, PEORIA, AZ 85382, (623) 738-0755) WHERE IT WAS DIAGNOSED THAT THE BRAKE BOOSTER AND BRAKE BOOSTER SWITCH NEEDED TO BE REPLACED. THE CONTACT STATED THAT THE VEHICLE WAS CURRENTLY AT THE DEALER TO BE REPAIRED. THE CONTACT STATED THAT THE FAILURE WAS INTERMITTENT. THE MANUFACTURER WAS NOTIFIED. THE APPROXIMATE FAILURE MILEAGE WAS 74,000.

NHTSA ODI 11040516

LOST BRAKING POWER. PEDAL HAS TO GO TO FLOOR TO WORK.

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BRAKE BOOSTER FAILURE BRAKE PEDAL HISSING AND STARTED TO STIFFEN I WAS DRIVING THEN STOPPED AT A TRAFFIC LIGHT NOTICED THAT THE BRAKES WERE HISSING AND WAS REALLY HARD TO PUSH ON TO A COMPLETE STOP

NHTSA ODI 11024282

SITTING AT A STOPLIGHT, MY BRAKE PEDAL CAME UP AND THE CAR DIED. RESTARTED IT, AND IT RAN FINE. HAPPENED AGAIN AT A STOPLIGHT. I TOOK IT TO A SHOP WHO SAID IT WAS A "MAZDA" ISSUE . WITHIN A WEEK, MY BRAKES STARTED TO NOT WORK. I TOOK IT TO MAZDA & THEY TOLD ME I WAS PAST THE 90,000 EXTENDED WARRANTY. I ASKED THEM WHY THEY WOULDN'T HONOR FIXING IT WHEN IT WAS A MAZDA ISSUE AND THEY JUST SAID I WAS PAST THE WARRANTY. BEWARE OF BUYING A "CERTIFIED USED CAR"! WARRANTIES/RECALLS WILL NOT BE SENT TO YOU!

NHTSA ODI 11021007

TL* THE CONTACT OWNS A 2011 MAZDA CX-9. WHILE DRIVING, THE BRAKES WERE APPLIED AND FAILED TO RESPOND. ADDITIONALLY, THE BRAKE PEDAL BECAME HARD TO DEPRESS. THE LOCAL DEALER WAS NOT CONTACTED. THE VEHICLE WAS NOT DIAGNOSED OR REPAIRED. THE MANUFACTURER WAS NOT NOTIFIED OF THE FAILURE. THE FAILURE MILEAGE WAS 60,000. *CN

NHTSA ODI 11011819

STIFF PEDAL. NO BRAKES

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MY CARS BRAKE PEDAL SUDDENLY BECAME STIFF AND WOULD NOT STOP MY CAR. I HAD TO SWERVE TO PREVENT MYSELF FROM REAR ENDING THE VEHICLE IN FRONT OF ME. AT THE NEXT STOP LIGHT I WAS EXTREMELY CAUTIOUS AND AFTER I FINALLY STOPPED, AS I WAITED FOR THE GREEN LIGHT THE CAR BEGAN IDLING ODDLY THEN IT STALLED. WAS ABLE TO START IT BACK UP. IT SEEMS TO BE SHIFTING A LITTLE ODDLY TOO. VERY SCARY DRIVING MY CAR. INCREDIBLY LUCKY WE WEREN'T INJURED NOR WAS ANYONE ELSE. WILL HAVE IT TOWED TO THE SHOP TO BE SAFE.

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TL* THE CONTACT OWNS A 2011 MAZDA CX-9. WHILE DRIVING APPROXIMATELY 30 TO 40 MPH, THE CONTACT ENGAGED THE BRAKE PEDAL AND ATTEMPTED MAKE A LEFT TURN, BUT THE BRAKES FAILED TO ENGAGE. THE CONTACT WAS ABLE TO STEER THE VEHICLE ONTO A DIRT ROAD TO BRING THE VEHICLE TO A STOP. THE VEHICLE WAS TOWED TO THE HYUNDAI MAZDA DEALER (14821 PANDELLI ROAD VICTORVILLE, CA 92392 PHONE 760-241-3801) WHERE IT WAS DIAGNOSED THAT THE BRAKE BOOSTER FAILED. THE MANUFACTURER STATED THAT THE BRAKE BOOSTER FAILURE WAS NOT WARRANTED FOR 90,000 MILES. THE VEHICLE WAS NOT REPAIRED. THE FAILURE MILEAGE WAS 90,000.

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HAD A PROBLEM A FEW YEARS AGO RELATED TO THE TRACTION CONTROL SYSTEM AS INDICATED BY THE WARNING LIGHT APPEARING ON THE DASH. DEALER CONTACTED THE WARRANTY DEPARTMENT TO FILE A CLAIM AND SAID THAT IS WOULD NOT BE COVERED UNDER WARRANTY BECAUSE THEY FELT IT WAS DUE TO DIRT AND NOT A FAULTY SENSOR. THE DEALER NEVER CONFIRMED ONE OR THE OTHER. SECOND ISSUE IS RELATED TO A HISSING NOISE COMING FROM THE BREAK PEDDLE. RESEARCH SUGGESTED MAZDA WAS INVESTIGATED BY NHTSA BACK IN 2014 AND INSTEAD OF A RECALL, MAZDA ISSUED AND EXTENDED WARRANTY FOR 7 YEARS OR 90K MILES. UNFORTUNATELY MY VEHICLE IS WITHIN THE 7 YEARS BUT NOT THE 90K. I AM CURRENTLY AT 97K MILES. STILL WAITING TO SEE IF MAZDA WILL COVER THE REPAIR OR AT LEAST DISCOUNT IT.

NHTSA ODI 10991513

WHILE DRIVING IN THE CITY OR ON HIGHWAY SUDDENLY THE BRAKE PEDAL BECOMES HARD TO PRESS AND CREEPS DOWN TO FLOOR WITH LOSS OF BRAKE BOOSTER, A HISSING NOISE IS HEARD IN THE CAR AND IT BECOMES VERY HARD TO STOP THE VEHICLE

NHTSA ODI 10959462

A STRANGE, HISSING NOISE COMING FROM THE PEDAL AREA. I AM HAVING A HARD TIME PUSHING THE PEDAL DURING 'INITIAL PEDAL APPLICATION', BUT THAT EFFORT DIMINISHED AS THE PEDAL WAS PRESSED FURTHER WHILE DRIVING. THE BRAKES BOOSTER SQUEALS VERY LOUD IF YOU PUSH THE BRAKES DOWN WHILE NOT MOVING. I DID SOME RESEARCH AND FOUND THIS IS A DEFECTIVE BRAKE BOOSTER ISSUE THAT MAZDA HAD CONFIRMED.

NHTSA ODI 10925619

BRAKE MASTER CYLINDER HISSING AND SQUEALING WHILE ENGINE IS IN IDLE. AFTER REVVING (AND RELEASING) TO 2000 RPM'S AND APPLYING (HOLDING) BRAKE PRESSURE SIMULTANEOUSLY, THE BUILD UP VACUUM PRESSURE DOES NOT ALLOW ENGINE TO RETURN TO IDLE RPM. RPM HANGS AT 1500 RPM'S. IF VEHICLE IS IN DRIVE WHILE ACCOMPLISHING THIS THEN THE BRAKE PRESSURE APPLIED IS NOT ENOUGH TO BRING THE VEHICLE TO A STOP. AFTER FIND THE CAUSE OF THE ISSUE I WENT ONLINE AND FOUND PREVIOUS MESSAGE BOARDS ABOUT THIS ISSUED WERE POSTED IN EARLY 2014 BUT A RECALL WAS NEVER ISSUED. REPORTED THE ISSUE TO MAZDA (20161012) BUT WAS TOLD THAT SINCE THE VEHICLE IS 30K OUTSIDE OF THE EXTENDED WARRANTY THEN THE ISSUE BELONGS TO THE CONSUMER. (MAZDAREF 1-368-227-539).

NHTSA ODI 10915597

AS I WAS DRIVING MY CAR ON A CITY STREET, I LOST ALL STEERING AND BRAKING ABILITY. THE FIRST TIME IT HAPPENED - MAZADA THOUGHT IT WAS A SUCTION FROM THE BRAKE AND A TUBE THAT WAS BROKEN. HOWEVER IT JUST HAPPENED AGAIN AS I WAS REVERSING IN A PARKING LOT. THE CAR IS NOW WITH MAZADA BEING LOOKED AT...

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DRIVING FROM WORK TODAY ON A HIGHWAY BEHIND AN ELECTRIC TRUCK THAT STOPPED ABRUPTLY, I APPLIED MY BREAKS KIND OF QUICKLY AND AFTER STOPPING AND TAKING OFF AGAIN WHEN TRYING TO APPLY BRAKES TO SLOW THE PEDDLE WOULD BE REALLY HARD TO PRESS AND IT FELT LIKE THE PEDDLE WAS PUSHING UP AGAINST YOU. THERE IS A HISSING NOISE WHEN BRAKE IS APPLIED AND IF YOU PRESS THE BRAKE ALL THE WAY TO THE FLOOR THERE IS A SQUEALING NOISE. THE HISSING NOISE IS INSIDE THE CARE AND SOUNDS TO BE COMING FROM AROUND THE BRAKE PEDDLE AREA. THE CAR CAN NOT BE DROVE AT THIS TIME BECAUSE WHEN IN MOVEMENT THE BRAKE IS REALLY HARD TO PRESS AND IT TAKES VERY LONG DISTANCES TO GET STOPPED. I CAN'T PUT MY CHILDREN IN THIS CAR TO GO ANYPLACE!

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THERE WAS A RATAL SOUND ANYTIME I WOULD GO OVER A BUMP OR DIP AT ANY SPEED. THE RATAL GOT LOUDER. I WENT TO MY MECHANIC AND HE SAID THE CALIPERS IN THE FRONT HAD TO BE REPLACED. SPECIFICALLY THE DRIVER'S SIDE IT LOOKED WORN AND THERE WAS RUST SO HE THOUGHT MOISTURE HAD GOT INTO THE CALIPERS. THOUGHT THIS WAS UNUSAL. SO BOTH HAD TO BE REPLACED IN ADDITION TO MY BRAKES. IT ALSO CAUSED MY BRAKES NOT TO FUNCTION CORRECTLYL.

NHTSA ODI 10904777

REFERENCE SSP93 - BRAKE BOOSTER DIAPHRAGM LEAKAGE ON 2010-2012 MAZDA CX-9 VEHICLES. ON, OR ABOUT AUGUST 5, 2016 POWER BRAKES FAILED, CAUSING A NEED TO APPLY HEAVIER THAN NORMAL PEDAL PRESSURE TO STOP VEHICLE, RESULTING IN VERY NEAR REAR-END COLLISION WITH VEHICLE AT STOP SIGN. THIS DEFECT IS KNOWN BY THE MANUFACTURER AND WAS INVESTIGATED BY NHTSA IN 2014. INVESTIGATION WAS CLOSED WITH NO RECALL ACTION RECOMMENDED. THERE SHOULD INDEED BE A RECALL MANDATED FOR THIS DEFECT SINCE IT CAN RESULT IN SERIOUS COLLISIONS DUE TO FAILURE TO SAFELY STOP VEHICLE.

NHTSA ODI 10896268

LOSS OF BRAKE FLUID; BRAKE PEDAL HARD TO PUSH & NOT STOPPING CAR; NOISE AT BRAKE PEDAL

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BRAKES RESIST WHEN TRYING TO STOP, TAKING LONGER TO COME TO COMPLETE STOP(AT ANY SPEEDS). ONCE STOPPED BRAKE COMPRESSES ALL THE WAY DOWN ON ITS OWN, FEELS LIKE THE CAR WILL START ROLL. WHEN APPLYING BRAKES IT MAKES AN AIR DECOMPRESSION SOUND. WHEN BACKING OUT OF PARKED POSITION AND BRAKING, CAR COASTS A LITTLE WHEN BRAKES ARE COMPLETELY PRESSED DOWN. VERY DANGEROUS ISSUE THAT I REALIZED WAS RELATED TO THE EXTENDED WARRANTY BRAKE BOOSTER ISSUE THAT I RECEIVED EARLIER IN THE YEAR. I ATTEMPTED TO GET THIS REPAIR AT THE FIRST SERVICE I SCHEDULED AFTER RECEIVING NOTICE AND MAZDA SERVICE DEPARTMENT REFUSED TO COMPLETE SERVICE BECAUSE THEY DIDN'T THINK MY CAR NEEDED IT.

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BRAKES HAVE SUDDENLY BECOME ERRATIC. OFTEN THEY ARE "HARD" AND REQUIRE EXCESSIVE PRESSURE TO GET THE VEHICLE TO STOP. MY RESEARCH SHOWS THIS IS A KNOWN ISSUE WITH THIS YEAR AND MODEL, AND MAZDA EXTENDED THEIR WARRANTY TO COVER THE ISSUE; HOWEVER, THAT EVIDENTLY DOES NOT APPLY TO SECOND OWNERS.

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