NHTSA owner reports · September 18, 2026 snapshot.
Service Brakes, Hydraulic complaints
31 reportsClear category filter50,600 miles · Jan 25, 2005
Service Brakes, Hydraulic
COMPLAINT RECEIVED VIA E-MAIL." I PURCHASED A 2000 AUDI S4 QUATTRO WITH 39K MILES ON IT FROM A NON-AUDI DEALER IN MARCH OF 2002. AT APPROXIMATELY 50,600 MILES MY ABS CONTROLLER FAILED. THIS IS INDICATED BY A DIAGNOSTIC TROUBLE CODE (DTC) IN THE VEHICLE'S ECU (COMPUTER) AS WELL AS 3 LOUD BEEPS WHEN YOU START THE CAR AND THE ABS L…
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COMPLAINT RECEIVED VIA E-MAIL." I PURCHASED A 2000 AUDI S4 QUATTRO WITH 39K MILES ON IT FROM A NON-AUDI DEALER IN MARCH OF 2002. AT APPROXIMATELY 50,600 MILES MY ABS CONTROLLER FAILED. THIS IS INDICATED BY A DIAGNOSTIC TROUBLE CODE (DTC) IN THE VEHICLE'S ECU (COMPUTER) AS WELL AS 3 LOUD BEEPS WHEN YOU START THE CAR AND THE ABS LIGHT STAYING LIT AND THE RED BRAKE LIGHT FLASHING CONSTANTLY. THIS PART HAS FAILED ON MULTIPLE AUDI S4'S OF THE SAME MODEL YEAR THAT I KNOW OF. AUDI WOULD NOT WARRANTY MY PART AS MY FACTORY WARRANTY HAD EXPIRED AT 50,000 MILES. THE PARTS ALONE COST APPROXIMATELY $1200 PLUS THE ADDITIONAL COST OF THE LABOR TO INSTALL THE PART. THE RESULTS OF THE ABS CONTROLLER'S MALFUNCTION IS THAT ESSENTIALLY, I DO NOT HAVE ANTI-LOCK BRAKING IN THE CAR, CAUSING UNDER HARD BRAKING THE POSSIBILITY OF LOCKING THE BRAKES. THIS HAPPENED ON NUMEROUS OCCASIONS. AUDI OF AMERICA HAS BEEN NOTIFIED BY NUMEROUS INDIVIDUALS OF THIS PARTICULARLY COMMON PROBLEM ON THE 2000 S4S, HOWEVER, TO DATE, NO RECALLS HAVE BEEN MADE." *JB
NHTSA ODI #10108866
48,125 miles · Jan 14, 2005
Service Brakes, Hydraulic
MY ABS CONTROLLER APPEARS TO BE FAILING. ABS WARNING LIGHT WILL COME ON AND GO OUT AT RANDOM TIMES. I HAVE 48,000 MILES ON THIS VEHICLE. SINCE THE ABS SYSTEM ACTS AS A PROPORTIONING VALVE BETWEEN THE FRONT AND REAR WHEELS, THE REAR WHEELS WILL LOCK UP UNDER MODERATE BRAKING WHEN THE LIGHT COMES ON. I CANNOT DIAGNOSE THE PROB…
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MY ABS CONTROLLER APPEARS TO BE FAILING. ABS WARNING LIGHT WILL COME ON AND GO OUT AT RANDOM TIMES. I HAVE 48,000 MILES ON THIS VEHICLE. SINCE THE ABS SYSTEM ACTS AS A PROPORTIONING VALVE BETWEEN THE FRONT AND REAR WHEELS, THE REAR WHEELS WILL LOCK UP UNDER MODERATE BRAKING WHEN THE LIGHT COMES ON. I CANNOT DIAGNOSE THE PROBLEM PROPERLY DUE TO THE RANDOM NATURE OF THE WARNING LIGHT. MANY SIMILAR REPORTS ON AUDIWORLD.COM ON THIS FAILURE. *JB
NHTSA ODI #10106303
89,250 miles · Dec 28, 2004
Service Brakes, Hydraulic
FAILED ABS CONTROLLER UNIT. ABS IS NONFUNCTIONAL. IN POOR WEATHER, MY BRAKES WILL LOCK UP. *JB
NHTSA ODI #10104675
67,000 miles · Nov 22, 2004
Service Brakes, Hydraulic
THE ABS AND BRAKE LIGHTS ON MY DASHBOARD INITIALLY FLASHED AND BEEPED INTERMITTENTLY, BUT NOW ARE ON CONSTANTLY. UPON RESEARCHING THE ISSUE, I'VE DISCOVERED THAT THIS IS A PROBLEM EXPERIENCED MY MANY OTHER MY2000 S4 OWNERS. THIS IS A SIGNIFICANT SAFETY ISSUE, AS THERE IS THE RISK THAT BRAKES MAY LOCK UP (EVEN WHEN RELEASING THE …
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THE ABS AND BRAKE LIGHTS ON MY DASHBOARD INITIALLY FLASHED AND BEEPED INTERMITTENTLY, BUT NOW ARE ON CONSTANTLY. UPON RESEARCHING THE ISSUE, I'VE DISCOVERED THAT THIS IS A PROBLEM EXPERIENCED MY MANY OTHER MY2000 S4 OWNERS. THIS IS A SIGNIFICANT SAFETY ISSUE, AS THERE IS THE RISK THAT BRAKES MAY LOCK UP (EVEN WHEN RELEASING THE PEDAL) UNDER BRAKING WHEN EXPERIENCING THESE SYMPTOMS. PLEASE TAKE ACTION ON THIS ISSUE. I KNOW MANY OWNERS WHO HAVE NO CHOICE BUT TO HOLD OFF ON THE REPAIR DUE TO THE AMOUNT BEING CHARGED BY DEALERS TO REPLACE THE PART (~$1700.00), EVEN THOUGH THE MOST LIKELY CULPRIT OF THE PROBLEM IS WIRING BETWEEN THE CONTROLLER AND THE ECU (<$1.00). *JB
NHTSA ODI #10100341
Mileage unknown · Sep 16, 2004
Service Brakes, Hydraulic
IT SEEMS THAT THERE IS A MANUFACTURING DEFECT AMONG B5 PLATFORM AUDI A4 VEHICLES, WHERE EITHER THE ABS CONTROLLER IS APT TO FAIL PREMATURELY, OR THE CONNECTION BETWEEN THE CONTROLLER AND THE INSTRUMENT CLUSTER FAILS. DUE TO THE HIGH FREQUENCY OF FAILURES, IT SEEMS HIGHLY UNLIKELY THAT THE ABS CONTROLLER IS AT FAULT AND PRONE TO…
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IT SEEMS THAT THERE IS A MANUFACTURING DEFECT AMONG B5 PLATFORM AUDI A4 VEHICLES, WHERE EITHER THE ABS CONTROLLER IS APT TO FAIL PREMATURELY, OR THE CONNECTION BETWEEN THE CONTROLLER AND THE INSTRUMENT CLUSTER FAILS. DUE TO THE HIGH FREQUENCY OF FAILURES, IT SEEMS HIGHLY UNLIKELY THAT THE ABS CONTROLLER IS AT FAULT AND PRONE TO SUCH A HIGH FAILURE RATE. WIRING TO THE INSTRUMENT CLUSTER SEEM TO BE THE MORE LIKELY CAUSE, YET DEALERS ALMOST EXCLUSIVELY DECIDE TO POINT TO THE CONTROLLER, WHICH COSTS UPWARDS OF $1200. THIS CONDITION IS UNDOUBTEDLY RISKY AND DANGEROUS. A MALFUNCTIONING ABS CONTROLLER CAN CAUSE THE REAR WHEELS OF THE VEHICLE TO LOCK UP UNDER HARD BRAKING, EVEN WHEN RELEASING THE BRAKE. *JB
NHTSA ODI #10091120
58,000 miles · Sep 14, 2004
Service Brakes, Hydraulic
ABS CONTROLLER ON A 2000 AUDI S4 FAILED AFTER 58K MILES. THE BRAKE FLUID PUMP AND ABS CONTROLLER UNIT ARE ALL IN ONE, AND THE COST FOR REPAIRS IS ABOUT $1700. IT IS MY BELIEF THAT THIS UNIT SHOULD NOT FAIL AFTER SUCH LOW MILEAGE. THE CAR IS UNDER FULL WARRANTY UP TO 50K MILES OR 4 YEARS, WHICHEVER COMES FIRST, BUT THESE UNITS…
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ABS CONTROLLER ON A 2000 AUDI S4 FAILED AFTER 58K MILES. THE BRAKE FLUID PUMP AND ABS CONTROLLER UNIT ARE ALL IN ONE, AND THE COST FOR REPAIRS IS ABOUT $1700. IT IS MY BELIEF THAT THIS UNIT SHOULD NOT FAIL AFTER SUCH LOW MILEAGE. THE CAR IS UNDER FULL WARRANTY UP TO 50K MILES OR 4 YEARS, WHICHEVER COMES FIRST, BUT THESE UNITS ARE KNOWN TO FAIL WITHIN THE FIRST 60K MILES, AND IN OTHER VEHICLES THEY LAST MUCH LONGER.
NHTSA ODI #10090986
Mileage unknown · Jul 26, 2004
Service Brakes, Hydraulic
WHILE APPLYING THE BRAKES PEDAL WENT TO THE FLOOR. CONSUMER WAS ABLE TO MAINTAIN CONTROL OF THE VEHICLE, AND DROVE IT HOME. ABS BRAKING LIGHT APPEARED ON THE DASHBOARD AND REMAINED ON. CONSUMER CONTACTED THE DEALERSHIP, AND WILL MAKE APPOINTMENT TO BRING THE VEHICLE IN FOR INSPECTION. *AK CONSUMER CONTACTED MANUFACTURER B…
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WHILE APPLYING THE BRAKES PEDAL WENT TO THE FLOOR. CONSUMER WAS ABLE TO MAINTAIN CONTROL OF THE VEHICLE, AND DROVE IT HOME. ABS BRAKING LIGHT APPEARED ON THE DASHBOARD AND REMAINED ON. CONSUMER CONTACTED THE DEALERSHIP, AND WILL MAKE APPOINTMENT TO BRING THE VEHICLE IN FOR INSPECTION. *AK CONSUMER CONTACTED MANUFACTURER BUT REFUSED TO ASSIST REPAIR OF VEHICLE. *LA
NHTSA ODI #10079366
59,520 miles · Jul 19, 2004
Service Brakes, Hydraulic
ABS CONTROLLER MODULE FAILURE - BOSCH 5.3 SYSTEM - 2000 AUDI S4. *JB
NHTSA ODI #10082219
Mileage unknown · Jul 6, 2004
Service Brakes, Hydraulic
PROBLEMS WITH ABS CONTROLLER ON 2000 AUDI S4.*MR ABS WARNING LIGHT WAS INTERMITTENTLY ON. *LA
NHTSA ODI #10081818
Mileage unknown · Mar 24, 2001
Service Brakes, HydraulicVehicle Speed ControlCrashInjury
ON OR ABOUT 11/20/00 I APPLIED BRAKES WHILE DRIVING DOWN HILL. CAR ACCELERATED OUT OF CONTROL. BRAKES WOULD NOT STOP CAR, WHICH EVENTUALLY CRASHED INTO TELEPHONE POLE. I INJURED MY LEFT LEG. AUDI ADVISED ME THEY KNEW OF NO "DEFECT" THAT COULD CAUSE THIS ACCIDENT. ON 13/21/01 AS I APPLIED BRAKES TO TURN INTO A PARKING SPACE CONTI…
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ON OR ABOUT 11/20/00 I APPLIED BRAKES WHILE DRIVING DOWN HILL. CAR ACCELERATED OUT OF CONTROL. BRAKES WOULD NOT STOP CAR, WHICH EVENTUALLY CRASHED INTO TELEPHONE POLE. I INJURED MY LEFT LEG. AUDI ADVISED ME THEY KNEW OF NO "DEFECT" THAT COULD CAUSE THIS ACCIDENT. ON 13/21/01 AS I APPLIED BRAKES TO TURN INTO A PARKING SPACE CONTIGUOUS TO A BUILDING THE VEHICLE ACCELERATED. WHEN I BOTH HEARD TO ENGINE RACING AND THE CAR ACCELERATING I FORTUNATELY SHIFTED INTO NEUTRAL AND STOPPED THE VEHICE. MY FOOT WAS NOT ON THE ACCELERATOR! I REFUSE TO DRIVE THIS VEHICLE. AUDI'S RESPONSE IS THAT IF THE DEALER FINDS A PROBLEM AUDI WILL TAKE APPROPRIATE ACTION. THERE IS A PROBLEM WHETHER AUDI FINDS IT OR NOT. I AM NOT RISKING A FATAL ACCIDENT TO ESTABLISH THIS FACT!*AK
NHTSA ODI #742955