2004 Mercedes-Benz SL500 Brakes Problems

The contact owns a 2004 Mercedes-Benz SL500. The contact stated that after starting the vehicle, the message "Brakes Reached Historic Threshold" was displayed, which indicated that the brake control unit had malfunctioned. Additionally, while depressing the brake pedal, the brake pedal was spongy, causing the stopping distance to become extended. The vehicle was taken to the local dealer and was diagnosed with brake control unit failure. The contact was informed that the brake control unit needed to be replaced. The vehicle was not repaired. The manufacturer was notified of the failure, but no assistance was provided. The contact stated that a 25-year warranty for the failure was previously issued by the manufacturer that was associated with the failure, but was not honored. The failure mileage was 62,800.

NHTSA ID

11754971

Incident

Jul 15, 2026

Mileage

62,800 mi

Question 1: The Sensotronic Brake Control (SBC) unit, which is a high-pressure "brake-by-wire" hydraulic system. Component A7/3. The component is currently installed in the vehicle and is available for inspection. Question 2: The vehicle experienced a sudden, catastrophic loss of hydraulic brake pressure while in operation. This failure required extreme physical force on the pedal and significant increase in stopping distance. The vehicle is currently in my garage with chocked wheels until I figure out what's next. A couple days ago, I had the car at a dealer and requested a review of this system and they released the car back to me stating the system status was, "OK" despite me stating to the dealer that the safety-monitoring counter was found to be at 0 on a 63,000-mile car. In all of my research, I believe this "silenced" the vehicle's ability to provide a timely service warning (Code C249F) before total hydraulic failure occurred. Question 3: Mercedes-Benz of Denver performed a diagnostic on January 21, 2026. While the dealer initially claimed the system was "OK," the total failure occurred within 72 hours of their inspection. The reason it was at Benz of Denver is because my independent mechanic confirmed the 0 actuation count which was suspicious to me. I wanted to understand the mechanical integrity of the newly purchased vehicle. Question 4: Yes, inspected by an authorized Mercedes-Benz dealership technician on January 21, 2026. Question 5: To my knowledge there were no mechanical symptoms prior to the red screen however, I cannot confirm or deny that as I had driven less than 1000 miles since I purchased the vehicle. I have no concept of how the braking "should have" felt. The only "symptom" was the technical data anomaly (the 0 actuation count) flagged by an independent shop, which I can attest the dealer refused to investigate fully. On January 24th, 2026, the RED dashboard warning appeared: "Reduced Brake Effect - Start Engine!".

NHTSA ID

11713126

Incident

Jan 24, 2026

THE VEHICLE HAS A BRACKET ON TOP OF THE GAS TANK THAT COMES DISENGADED AND CAUSES THIS DISTINCTIVE NOISE WHICH SOUNDS LIKE SOMETHING SWINGING AND TAPPING AGAINST THE GAS TANK AND I HAS TO HAPPEN A LOT DUE TO EVERY SERVICE I HAVE BEEN ASKED ABOUT THE PROBLEM. IT ALSO HAS TO BE SOMETHING WITH MULTIPLE VEHICLES DUE TO ONLINE MERCEDES OWNERS ARE HAVING THE SAME PROBLEM. THE SOUND IS REALLY DISTURBING AND I WOULD LIKE AN ANSWER AS TO WHAT TO DO. THANKS [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6).' *PM

NHTSA ID

11208386

Incident

May 1, 2012

Mileage

60,000 mi

I SUBMITTED VIA FAX EARLIER THIS WEEK A FORMAL LETTER TO MR. EXLER THE PRESIDENT & CEO OF MBUSA AND, CC'D MR. KING OF THE NHTSA THAT INCLUDED INFORMATION ABOUT KNOWN CRITICAL SAFETY ISSUED THESE VEHICLES HAD PRIOR TO MBUSA IMPORTING THEM TO THE UNITED STATES. MBUSA FAILED TO DISCLOSE THESE KNOWN ISSUES AND, CHOSE TO IMPORTATION THESE VEHICLES VIOLATING VEHICLE IMPORTATION RULES. YESTERDAY-JANUARY 31, 2019 I RECEIVED A CALL FROM A REPRESENTATIVE OF MBUSA STATING HE WAS CALLING ON BEHALF OF MR. EXLERS OFFICE CONCERNING MY LETTER. I WILL NOT BE INTIMIDATED BY MBUSA WHILE SEEKING THE TRUTH ON WHY MBUSA ALLOWED THESE VEHICLES TO ENTER THE USA KNOWING THESE CRITICAL SAFETY ISSUES EXISTED WHILE MISLEADING CONSUMERS AND, THE NHTSA. ON JANUARY 21, 2019 MY VEHICLE HAD WHAT IS DESCRIBED BY MBUSA AS A CATASTROPHIC FAILURE WHEN THE ENTIRE BRAKE SYSTEM FAILED. THIS FAILURE COULD HAVE KILLED ME - AND, OTHER MOTORIST. MBUSA HAS REPLACED THE SBC UNIT AT LEAST 6 TIMES AND, STILL THE ISSUE AND, OTHER PERSIST. THE VEHICLE HAS BEEN DRIVEN ON AVERAGE 4,000 MILES ANNUALLY. HOW MANY FAILURES MUST HAPPEN BEFORE MBUSA IS FULLY INVESTIGATED? THEY REFUSED TO PROVIDE ME ANY INFORMATION ON THE VEHICLES EXCEPT THE 4 YEAR WARRANTY PERIOD. ONCE I COMPLETE MY RESEARCH ON THESE VEHICLES I WILL SUBMIT MY FINDINGS TO THE NHTSA & MS. KING

NHTSA ID

11173505

Incident

Jan 21, 2019

Mileage

61,000 mi

DUE TO DETERIORATION OF THE WIRING HARNESS CONNECTION OR FAILURE OF THE HYDRAULIC PUMP, THE SENSOTRONIC BRAKE CONTROL (SBC) SYSTEM MAY DEFAULT TO THE HYDRAULIC BACK-UP MODE. IN THE BACK-UP MODE, THE DRIVER HAS BRAKING POWER SUFFICIENT TO STOP THE VEHICLE, BUT GREATER BRAKE PEDAL PRESSURE IS REQUIRED AND BRAKE PEDAL TRAVEL WILL BE NOTICEABLY LONGER. DEALERS WILL INSTALL A BRACKET AND REPLACEMENT GROUND WIRE TO THE SBC PUMP UNIT ON ALL AFFECTED VEHICLES. ADDITIONALLY, DEALERS WILL INSPECT AND REPLACE THE SSC PUMP UNIT IN CERTAIN SL MODELS. THE MERCEDES-BENZ RECALL NUMBERS ARE 2005070007 AND 2005110001. RESEARCH SHOWS ONLY 59% OF THE 100% REQUIRED RECALL WAS DONE PROPERLY BY AN AUTHORIZED DEALER. THIS ISSUE WAS NOT DISCLOSED WHEN I PURCHASED THIS CAR AND, THE REQUIRED WORK WAS NOT DONE AND, MERCEDES SAID THE 60 DAYS FROM RECALL HAD PASSED - YET THE REPORTS SENT TO NHTSA BY MERCEDES BENZ APPEARS TO BE FALSE DATA - THIS SHOULD BE INVESTIGATED.

NHTSA ID

11142891

Incident

Jun 22, 2004

I PURCHASED THIS VEHICLE IN 2014. MY BRAKES COMPLETELY WENT OUT WHILE DRIVING JANUARY 1 2018. I WAS ATTEMPTING TO STOP AT AN INTERSECTION WHEN THE THE VEHICLE WOULD NOT STOP WITH ONCOMING TRAFFIC ON BOTH SIDES COMING TOWARDS ME. I IMMEDIATELY PRESSED THE ACCELERATOR AND SPED THROUGH THE INTERSECTION TO AVOID AN ACCIDENT....ABSOLUTELY TERRIFYING AND WITHOUT ANY WARNING WHATSOEVER. BECAUSE THE DEALERSHIP WAS CLOSED I WAS UNABLE TO SEEK SERVICE THAT DAY. I CALLED MERCEDES OF RICHMOND VA BEING THAT WAS THE CLOSEST DEALERSHIP WHERE I WAS VISITING AT AT THE TIME. UNFORTUNATELY I COULD NOT GET AN APPOINTMENT UNTIL JANUARY 3RD. I HAD IT TOWED THAT MORNING AND THEY CAME BACK HOURS LATER NOTIFYING ME IT WAS IN FACE THE SBC SYSTEM WHICH NEEDED TO BE REPLACED AT THE COST OF $2006. I WAS OUTRAGED LEARNING THAT MBUSA KNEW OF THIS ISSUE NHTSA CAMPAIGN NUMBER 04V296000 IN JUNE 2004 BUT CLOSED IT OUT IN DECEMBER 2013. I DID NOT PURCHASE THE VEHICLE UNTIL 2014. I ASKED IF THERE WAS ANYTHING THEY COULD DO TO ASSIST ME AS ONE OF THE ASSOCIATES INFORMED ME ABOUT "GOOD WILL" SERVICE WHERE THEY MIGHT CONSIDER MY SITUATION AND HELP. I WAS AGAIN EXTREMELY DISAPPOINTED TO LEARN THEY WOULD ONLY ASSIST WITH $300 AS WE HAVE 2 MERCEDES AND HAVE INCURRED THOUSANDS OF DOLLARS IN KNOWN REPAIR ISSUES OF THE FEW YEARS. I AM ASKING THAT MBUSA ACCEPT THE COST OF THIS REPAIR AS IT WAS A KNOWN ISSUE THAT THEY WERE REPLACING AT NO COST TO OWNER. I HAVE 131,000 MILES ON THE CAR WHICH IS UNDER MILEAGE FOR THAT YEAR. THEY TOLD ME TO ASK MERCEDES IF THEY WOULD CONSIDER ASSISTING IN ANY WAY BUT THEY SAID THERE WAS NOTHING THEY COULD DO.

NHTSA ID

11058517

Incident

Jan 1, 2018

Mileage

131,000 mi

BRAKES FAIL...WARNING LIGHT ONLY AFTER YOU HAVE NO BRAKES...A SUICIDE MACHINE IN TRAFFIC

NHTSA ID

10945048

Incident

Dec 28, 2016

Mileage

61,230 mi

WAS TRAVELING BEHIND ANOTHER VEHICLE AT APPROXIMATELY 35 MPH AROUND 6PM WHEN TRAFFIC AHEAD BEGUN TO SLOW AND STOP FOR THE TRAFFIC LIGHT SIGNAL A CHANGE, UPON ATTEMPTING TO STOP THE ABS BRAKE SYSTEM FAILED AND ONLY GAVE A WARNING UNTIL AFTER MY VEHICLE REAR ENDED THE CAR IN FRONT OF CAUSING ME BET THROWN VIOLENTLY FORWARD AND BACKWARD WHICH, GAVE RISE TO WHIPLASH INJURY, DAMAGING THE FRONT END OF MY VEHICLE AND THE REAR END OF THE VEHICLE IN FRONT WITH SIMILAR INJURIES THE DRIVER OF THE VEHICLE IN FRONT OF ME. *TR

NHTSA ID

10654090

Incident

Oct 24, 2014

Mileage

100,560 mi

I WAS TRAVELING IN TRAILING A SAFE DISTANCE BEHIND ANOTHER VEHICLE AT A SPEED OF ABOUT 35 MILES PER HOUR AND AS WE APPROACHED S TRAFFIC SIGNAL, ALL CARS BEGUN TO SLOW FOR THE YELLOW LIGHT IN ORDER TO PREPARE FOR A SAFE STOP. HOW EVER, UPON MY ATTEMPTING TO STOP THE BRAKES SUDDENLY FAILED AND AN A RED WARNING LIGHT CAME ON "STOP" MY VEHICLE FAILED TO STOP AND I COLLIDED INTO THE VEHICLE IN FRONT OF ME CAUSING INJURY TO THE OTHER DRIVER AND MYSELF. THERE WAS NEVER A WAD AILEDHNING LIGHT THAT THE ABS SYSTEM WAS FAILING. *TR

NHTSA ID

10649567

Incident

Oct 24, 2014

Mileage

100,030 mi

TL* THE CONTACT OWNS A 2004 MERCEDES BENZ SL500. WHILE DRIVING APPROXIMATELY 2 MPH, A WARNING LIGHT SUDDENLY FLASHED THAT INDICATED THAT THE BRAKES WERE FAULTY. THE CONTACT DEPRESSED THE BRAKE PEDAL TO STOP THE VEHICLE, BUT THE BRAKES MALFUNCTIONED AND INCREASED THE STOPPING DISTANCE. THE DEALER STATED THAT THE ELECTRONIC BRAKE BOOSTER WAS FAULTY. THE MANUFACTURER WAS NOTIFIED, BUT NO SOLUTION WAS OFFERED. THE FAILURE MILEAGE WAS 82,000.

NHTSA ID

10644475

Incident

Oct 6, 2014

Mileage

82,000 mi

TL*THE CONTACT OWNS A 2004 MERCEDES BENZ SL500. WHILE DRIVING APPROXIMATELY 10 MPH, THE BRAKES FAILED. THE CONTACT DROVE THE VEHICLE UP A HILL IN ORDER TO STOP AND THEN PULLED INTO HIS DRIVEWAY. THE DEALER WAS NOTIFIED. THE CURRENT AND FAILURE MILEAGES WERE 3,200.

NHTSA ID

10214154

Incident

Jan 7, 2008

Mileage

3,200 mi