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

Brake booster failure. The power assisted braking has stopped working. There are no leaking vacuum hoses and the check valve is working. The brake pedal travels to the floorboard.

NHTSA ODI 11620856

The contact owns a 2011 Mazda CX-9. The contact stated while driving 20 MPH, there was an abnormal sound coming from the brakes. The contact stated that the brake pedal was firm and difficult to depress while attempting to stop the vehicle. The vehicle was not diagnosed or repaired. The manufacturer was contacted, and a case was filed. The failure mileage was 67,000.

NHTSA ODI 11506010

Braking trouble recent in weeks in 2011 Mazda CX-9 vehicle. Had mechanic (Euro Motorsports in Chagrin Falls OH) check it out. Turned out to be a faulty Brake Booster. Mechanic test drove car; braking failed and he almost rear-ended another vehicle. He found on line a Mazda service notice dating from April 4, 2014 called SSP93. Mazda issued an extended warranty of 7 years or 90,000 miles, whichever came first, to have defective part replaced by an improved part. But we were never informed by Mazda of Bedford, where we bought the vehicle. Currently, our vehicle has about 83,000 miles. Never knew there was a problem until recent trouble with the braking. There are thousands of CX-5, Cx-7, and Cx-9 vehicles in operation in U.S. right now; probably many owners have no idea there is a brake defect in their vehicles that could cause a serious accident, potentially fatal. Mazda should have done a recall in 2014, not an extended warranty. Although Brake Boosters are supposedly good for at least 150,000 miles of driving, our brake failure at around 83,000 miles proves otherwise. NHTSA should order Mazda to recall all vehicles with the defective brake part and replace them at Mazda's expense, probably hundreds of dollars each time. We do not want to have our brake booster replaced by our regular Euro Motosports mechanics because a recall must typically be repaired by the dealer. We already filed a complaint with State of Ohio Attorney General's office, but their people say the complaint must first go through BBB. No urgency on their part at all, even when informed potentially fatal flaw in the brakes. To avoid dangerous accidents, NHTSA should act more swiftly. Thanks.

NHTSA ODI 11487622

SIRT: I PURCHASED MY 2011 MAZDA CX 9 FROM MY CLOSE FRIEND [XXX] ON DEC.05 OF 2014! [XXX] HAD NOT BEEN ISSUED A SPECIAL SERVICES PROGRAM ABOUT THE BRAKE BOOSTER! WELL I NEVER RECEIVED THIS INFO EITHER? IN FACT I HAD TWO RECALL THAT WERE TAKEN CARE OF BY THE LOCAL MAZDA DEALER HERE IN THOUSAND OAKS CALIF. THIS KNOWN BRAKE BOOSTER DETONATION HAS BEEN KNOWN BY MAZDA.IOT IS A VERY DANGEROUS CONDITION AND IS NOT TO SAFE TO DRIVE THE CAR AT ALL- I WILL NOT DRIVE THE CAR AND SEETHE ORIGINAL MATTER SHOULD HAVE BEEN LET IT BE KNOWN TO MYSELF AND FEEL THE MATTER SHOULD BE ADDRESSED ASAP BY MAZDA -THANK YOU [XXX] ADDING BACKING -VERY HARD BRAKE - WHEN DRIVING IT HAD TO REALLY STAND HARD ON THE BRAKE TO STOP CAR B! ALL INDICATIONS POINT TO A BRAKE BOOSTER FAILURE ! TO SUMMARIZE IO WAS NEVER NOTIFIED BY MAZDA ABOUT THE SPECIAL SERVICE PROGRAM FOR THE REPAIR OF THIS EXTREMELY UNSAFE BRAKE PROBLEM! INFORMATION Redacted PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).

NHTSA ODI 11406762

THE BRAKE PEDAL SEEMS HARD TOO STOP THE CAR WHEN IN MOTION ON PUBLIC STREETS, VEHICLE CONTINUES TOO ROLL UPON PUMPING BRAKES, HAVE TOO CONTINUOUSLY PUMP THE BRAKE HARD TOO STOP THE VEHICLE, HAD THE FRONT BRAKES REPLACED RECENTLY, AND BRAKE PEDAL IS STILL NOT FUNCTIONING CORRECTLY, POSSIBLY THE BRAKE BOOSTER.

NHTSA ODI 11351938

I WENT FROM HAVING BRAKES TO HAVING TO PUSH THE BRAKE TO THE FLOOR, WHICH STILL DID NOT STOP THE CAR, ALL IN THE SAME DAY. I WAS LUCKY NOT TO WRECK BUT COULD NOT STOP FOR STOP SIGNS OR STOP LIGHTS ALL WHILE MY 22 MONTH OLD WAS IN THE VEHICLE. SOMETHING IN THE BRAKE SYSTEM MESSED UP, AND IT STILL HAD A FULL THING OF BRAKE FLUID. I BELIEVE THAT IT IS THE BRAKE BOOSTER CAUSING THIS PROBLEM. *TR

NHTSA ODI 11327780

BRAKES WHEN APPLIED WOULD SOMETIMES GO TO THE FLOOR BEFORE STOPPING. THE BRAKE BOOSTER HAS GONE BAD AND VERY DANGEROUS ALMOST CAUSING AN ACCIDENT. BRAKE PEDAL SOFT AND SOMETIMES WILL NOT STOP.

NHTSA ODI 11311569

BRAKES REALLY HARD TO PRESS. WIFE THOUGHT CAR WASN'T GOING TO STOP AND SHE WAS GOING TO REAR END CAR IN FRONT OF HER. SOMETIMES BRAKE PEDAL WOULD FEEL SPONGY. OVER LAST MONTH THERE WAS AN INTERMITTENT STRANGE NOISE SOMETIMES WHEN CAR WAS STARTED. MAZDA DEALERSHIP IDENTIFIED THE PROBLEM TO BE A DEFECTIVE BRAKE BOOSTER. I FOUND THAT NHTSA OPENED INVESTIGATION ON CX-9 BRAKE ISSUES PREVIOUSLY AND MAZDA IDENTIFIED PROBLEM TO BE BRAKE BOOSTER. MAZDA EXTENDED THE WARRANTY TO 7 YEARS OR 90,000 MILES AND NHTSA CLOSED INVESTIGATION. OUR BRAKE BOOSTER FAILED AT 9 YEARS WITH 79,388 MILES ON THE CAR. FROM WHAT I HAVE READ THE LIFE EXPECTANCY OF A BRAKE BOOSTER IS THE LIFE OF THE CAR. MAZDA NEVER INFORMED US ABOUT THIS POSSIBLE PROBLEM. OUR FAMILY COULD HAVE BEEN SERIOUSLY INJURED OR KILLED DUE TO THIS DEFECT. WHY DID THE NHTSA ACCEPT AN EXTENDED WARRANTY AS A SOLUTION?

NHTSA ODI 11297398

TL* THE CONTACT OWNS A 2011 MAZDA CX9. THE CONTACT STATED THAT WHILE HIS WIFE WAS DRIVING APPROXIMATELY 13 MPH AND ATTEMPTING TO SLOW DOWN, THE BRAKE PEDAL WAS HARDER THAN USUAL TO DEPRESS. AS A RESULT, THE DRIVER REAR ENDED THE VEHICLE IN FRONT CAUSING A FIVE VEHICLE COLLISION AT A TRAFFIC LIGHT. NONE OF THE FRONTAL AIR BAGS DEPLOYED. THE POLICE WERE PRESENT AND A POLICE REPORT WAS FILED. THERE WERE NO INJURIES REPORTED. THE VEHICLE WAS TOWED TO AN IMPOUND LOT WHERE THE INSURANCE COMPANY WAS SCHEDULED TO HAVE AN INSPECTOR INSPECT THE VEHICLE. THE VEHICLE WAS NOT TAKEN TO THE DEALER FOR A DIAGNOSTIC. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS NOT NOTIFIED OF THE FAILURE. THE CONTACT REFERENCED NHTSA ACTION NUMBER: PE14005 (SERVICE BRAKES, HYDRAULIC). THE VIN WAS NOT AVAILABLE. THE APPROXIMATE FAILURE MILEAGE WAS 86,000.

NHTSA ODI 11296688

BRAKE BOOSTER IS LEAKING. TAKES LONGER TO STOP. CALLED MAZDA AND REPORTED ISSUE.

NHTSA ODI 11271487

BRAKE PEDAL IS VERY HARD AND VEHICLE IS NOT STOPPING WELL ALMOST CAUSING AN ACCIDENT

NHTSA ODI 11258920

OUR VEHICLE HAS LOST BRAKING POWER AND IS UNSAFE TO DRIVE ANY DISTANCE NOW. IT IS VERY DIFFICULT TO GET THE VEHICLE TO STOP AND KEEP IT STOPPED ONCE IT HAS STOPPED MOVING WITHOUT PUTTING IT IN PARK. I HAVE BEEN ADVISED THIS IS IN RELATION TO MAZDA SSP 93. MAZDA HAS ADVISED THAT IS IT MY RESPONSIBILITY TO HAVE THIS VEHICLE TOWED TO THE NEAREST DEALERSHIP, PAY FOR REPAIR LABOR, AND PAY FOR A RENTAL CAR WHILE REPAIRS ARE BEING MADE. I AM IN COMPLETE DISBELIEF THAT A KNOWN MANUFACTURER'S DEFECT RELATED TO BRAKING AND GENERAL SAFETY OF EVERYONE ON THE ROAD WAS NOT IMMEDIATELY ISSUED AS A RECALL. WE WERE PROVIDED ZERO NOTICE THAT THERE WAS EVEN POTENTIAL FOR BRAKE FAILURE.

NHTSA ODI 11259062

WHEN TRYING TO STOP AT AN INTERSECTION, THE BRAKES DID NOT RESPOND AS USUAL. EVEN WITH PRESSING THE BRAKE PEDAL AS HARD AS I COULD, THE STOPPING DISTANCE INCREASED BY AT LEAST 30 FEET WHICH PLACED ME IN THE MIDDLE OF THE INTERSECTION. THIS IS WORSE IN HOT CONDITIONS. THERE IS ALSO A HISSING NOISE WHEN THE BRAKE PEDAL IS DEPRESSED. THIS CONTINUES TO HAPPEN AND DOES NOT FEEL SAFE TO DRIVE. A MECHANIC SAID IT MAY BE THE POWER BRAKE BOOSTER. I NOTICED THAT THIS WAS INVESTIGATED, MAZDA ISSUED A SPECIAL SERVICE PROGRAM WHICH ENDED IN 2015. THE LETTER ISSUED AT THAT TIME SAID IT WAS NOT NECESSARY TO TAKE ACTION UNLESS THERE WAS A PROBLEM AT THAT TIME. MAZDA SHOULD EXTEND THE SERVICE PROGRAM BECAUSE THIS IS CLEARLY A SAFETY ISSUE.

NHTSA ODI 11229162

I NOTICED A SIGNIFICANT PROBLEM BRAKING ON MY CX9 TO WHERE I HAD TO ALMOST STAND ON THE BRAKE PEDAL TO STOP. ADDED BRAKE FLUID HOPING THAT WOULD HELP BUT DID NOT. TOOK IT TO MAZDA DEALERSHIP IN BUFORD,GA AND THEY CONFIRMED THE BRAKE BOOSTER WAS CAUSING THE PROBLEM AND STRONGLY RECOMMENDED REPLACEMENT ASAP. THEY EXPLAINED THE PROBLEM IS A KNOWN ISSUE AND MAZDA EXTENDED THE WARRANTY TO 90K MILES. THE PROBLEM FOR ME WAS MY '11 CX9 HAD 107K. I HAD NO CHOICE BUT TO PAY TO HAVE THE PROBLEM FIXED DUE TO MY PERSONAL SAFETY. A COUPLE DAYS LATER I CALLED MAZDA CUSTOMER EXPERIENCE AND VOICED MY DISAPPOINTMENT THAT THIS PART WAS NEVER RECALLED AND PEOPLE ARE DRIVING AROUND IN UNSAFE CX9'S. THEY DID CONFESS THAT IF I WOULD HAVE CALLED THEM 'BEFORE' MY REPAIR THEY COULD HAVE REVIEWED THE ISSUE AND PERHAPS OFFSET SOME OF THE COST. THIS LEFT ME VERY DISAPPOINTED SINCE THEY WOULD HAVE PREFERRED I KEPT DRIVING THE CAR AND RISKED INJURY TO OTHERS WHILE THEY REVIEWED THE CASE. #CX9SADNESS

NHTSA ODI 11207231

TL* THE CONTACT OWNS A 2011 MAZDA CX-9. THE CONTACT STATED THAT THERE WAS AN INTERMITTENT FAILURE WITH THE BRAKE SYSTEM FAILING TO FUNCTION PROPERLY AS THE CONTACT HAD TO PRESS THE BRAKE PEDAL, RELEASE THE BRAKE PEDAL AND APPLY FORCE TO STOP THE VEHICLE. THE FAILURE HAPPENED MORE THAN ONCE TO THE POINT OF IT BEING A RISK THAT MAY RESULT IN A CRASH. IN ADDITION, THE VEHICLE STALLED. THE VEHICLE WAS UNSAFE TO DRIVE, PARKED AT THE OWNER'S RESIDENCE AND MAY NEED TO BE TOWED FOR REPAIRS. THE DEALER YOUNG MAZDA (191 COMMERCE PARK DR, EASTON, PA 18045, (610) 991-9100) WAS NOTIFIED OF THE FAILURE. THE VEHICLE WAS NOT DIAGNOSED. THE VEHICLE WAS NOT INCLUDED IN NHTSA ACTION NUMBER: PE14005 (SERVICE BRAKES, HYDRAULIC). THE MANUFACTURER WAS NOTIFIED OF THE FAILURE TO DETERMINE IF THEY HAD A TECHNICAL GUIDELINE TO REPAIR THE VEHICLE. THE VIN WAS NOT AVAILABLE. THE APPROXIMATE FAILURE MILEAGE WAS NOT AVAILABLE.

NHTSA ODI 11206546

BRAKE BOOSTER FAILURE

NHTSA ODI 11204252

IN DEC. 2018, I HAD MY 2011 MAZDA CX-9 TO A MAZDA DEALER SERVICE SHOP FOR WHAT I FELT LIKE A SPONGY BRAKE PEDAL. WHEN I PICKED UP THE CAR THE SERVICE ADVISOR TOLD BE THERE IS NOTHING WRONG WITH THE CAR'S BRAKES. AFTER A FEW MONTHS, WHILE THE SYMPTOM PERSISTED, I FOUND OUT THERE IS A KNOW ISSUE WITH THE BRAKE BOOSTER, WHICH MAZDA ACKNOWLEDGED AND ISSUED A WARRANTY EXTENSION (WHICH IS EXPIRED NOW). TWO DAYS AGO, WHILE TRAVELING IN TRAFFIC ON HIGHWAY, I HAD TO STOP THE CAR DUE TO A SUDDEN TRAFFIC JAM AND I FELT THE BRAKES BEING INSUFFICIENTLY EFFECTIVE TO STOP MY CAR SAFELY. AS SUCH, I PUMPED THE BRAKE PEDAL 3-4 TIMES AND THAT CAUSED THE PEDAL TO BECOME VERY HARD AND MADE MATTERS WORST- TO A POINT WHERE I HAD TO PULL ON THE SHOULDER TO AVOID REAR-ENDING THE VEHICLE IN FRONT OF ME.

NHTSA ODI 11195633

MAZDA CX-9 2011 HAS UN-DETECTED WATER PUMP LEAKS WHICH CAUSE TO ENGINE OVERHEAT AND EVENTUAL ENGINE DEATH. MAZDA CORPORATE IS UNWILLING TO CO-OPERATE. CAR SUDDENLY CAME TO A HALT SHOWING ENGINE LIGHT ON..AND I HAD TO REPLACE THE BRAKE BOOSTER ALSO BECAUSE WHEN I WAS DRIVING THE VEHICLE IT TURN OFF ON ME EVERYWHERE AND I HAD TO PAY OUT OF MY POCKET AND IM STILL PAYING FOR THIS VEHICLE RIGHT NOW MY VEHICLE IS IN A GARAGE BECAUSE IS NOT DRIVABLE

NHTSA ODI 11183329

DIFFICULTY PUSHING THE BRAKE PEDALS AND ACHIEVING A FULL STOP. SOMETIMES CAR WOULD INCH FORWARD WHEN BRAKE APPLIED. SOMETIMES HEARING A HISSING NOISE WHEN TRYING TO APPLY THE BRAKES. THE NOISE SEEMED TO COME FROM THE AREA OF THE BRAKE PEDAL. OVERALL, BRAKES DID NOT APPEAR TO BE WORKING AS INTENDED. PRIMARILY EXPERIENCED AT LOWER SPEEDS. HAS HAPPENED REPEATEDLY OVER A FEW WEEKS.

NHTSA ODI 11181611

I STARTED NOTICING IT WAS TAKING A LONG DISTANCE FOR MY VEHICLE TO COME TO A STOP. I TOOK IT TO MY MECHANIC. WE TOOK IT FOR A TEST DRIVE AND HE CONFIRMED THERE WAS A PROBLEM WITH THE POWER BRAKE BOOSTER. WHEN HE WAS DRIVING, IF HE PRESSED ON THE BRAKE PEDAL HARD, HE COULD MAKE THE CAR HAVE A LONG "BEEP" SOUND. OTHERWISE, HE, TOO, NOTICED THE LONG DISTANCE REQUIRED FOR THE CAR TO STOP.

NHTSA ODI 11172750

BRAKE PEDAL IS ROCK HARD AND TAKES IMMENSE PRESSURE TO PRESS DOWN TO GET BRAKES TO ENGAGE. HISSING NOISE COMING FROM UNDER DASH IT SEEMS.

NHTSA ODI 11151025

LOSS OF POWER BRAKES. EXCESSIVE BRAKE PEDAL PRESSURE NEEDED TO STOP VEHICLE. HISSING NOISE WHEN DEPRESSING BRAKE PEDAL.

NHTSA ODI 11139005

I WAS APPROACHING AN INTERSECTION WHERE I NEEDED TO STOP WITH MY CHILDREN IN THE CAR, I WENT TO HIT MY BRAKE PEDAL AND IT WAS STUCK IN THE UP POSITION AND I COULDN'T STOP, I HAD TO QUICKLY TURN MY WHEEL TO HIT THE SHOULDER OF THE ROAD TO SLOW DOWN AND TO AVOID BEING HIT IN THE INTERSECTION. THE CAR BRAKE THEN EVENTUALLY RELEASED AFTER HEARING A HISSING NOISE AND IT SLOWLY GOING INTO THE DOWN POSITION. WHEN I HAD A MECHANIC LOOK AT IT, HE EXPLAINED THAT IT CLEARLY IS A FAILURE OF THE BRAKE BOOSTER. WE RESEARCHED IT AND FOUND THAT SIMILAR ISSUES HAPPENED WITH MY MAKE AND MODEL IN THE PAST BUT MAZDA DOES NOT WANT TO HONOR THE DEFECT AS ITS SPECIAL SERVICE CALL ON IT ENDED IN 2015.

NHTSA ODI 11128392

BRAKE BOOSTER FAILURE, CAUSING BRAKES TO NOT ENGAGE WITHOUT PUMPING THE BRAKE PEDAL. NO CHECK ENGINE OR MAINTENANCE LIGHTS WERE TRIGGERED DUE TO THE FAILURE. ONLY INDICATION WAS ENGINE REVVING WHILE IDLE FOR NO APPARENT REASON AND INABILITY TO BRING THE VEHICLE TO A STOP.

NHTSA ODI 11123280

UNINFORMED ABOUT THE 2011 MAZDA CX9 BRAKE PROBLEM WHICH DID NOT SHOW UP UNTIL 8-22-2018, I WAS INFORMED THAT WHILE MAZDA EXTENDED THEIR WARRANTY, THE WARRANTY HAD ENDED IN 4-2018 OR WHEN THE CAR HAD 90,000 MILES LOGGED. (MY CAR IS AT 91,244 MILES.) THE CAR IS UNSAFE TO DRIVE, THE BRAKES ARE SUDDENLY NOT WORKING, AND THIS IS A DOCUMENTED PROBLEM WITH MY MAKE, MODEL, AND YEAR. THERE IS NO MORE IMPORTANT SAFETY FEATURE IN YOUR CAR THAN THE BRAKES. YES, TEENAGE DRIVERS ' THAT'S EVEN MORE IMPORTANT THAN BLUETOOTH CONNECTIVITY. UNFORTUNATELY, OWNERS OF THE 2010-2011 CX-9 HAVE BEEN HAVING PROBLEMS BRINGING THEIR CAR TO A STOP. THE BRAKE SYMPTOMS CX-9 OWNERS, ESPECIALLY THOSE IN HOTTER CLIMATES, HAVE BEEN TELLING HARROWING TALES OF BRAKE PROBLEMS CENTERED AROUND: THE BRAKES BECAME HARD TO PUSH, THERE WAS A HISSING NOISE FROM THE PEDAL AND THE CAR WOULD NOT STOP UNTIL THE BRAKE PETAL WAS PUMPED.

NHTSA ODI 11121818