RoadVitals

2004 Mercedes-Benz SL600 Problems

Owner-reported complaints filed with NHTSA, grouped by component

Data refreshed

Owner complaintsComplaints are reports submitted to NHTSA by owners and drivers. NHTSA does not verify most reports before publishing them, and a complaint does not establish that a defect exists. Volume is influenced by how many of a vehicle were sold, how long it has been on the road, and how much attention an issue has received.
4
Latest Dec 3, 2025
Components namedHow many of our component categories appear on at least one report for this model year. One report can name several.
3
Crash or fire reportedComplaints whose submitter recorded that a crash or a fire occurred. These are the reporter's own answers on the NHTSA form, not verified findings.
0

What this page shows

Everything below is an owner-reported complaint submitted to NHTSA about the 2004 Mercedes-Benz SL600, grouped by the component NHTSA recorded on the report. These are not confirmed defects, and they are not recalls. NHTSA does not verify most reports before publishing them, and a category with more reports in it is not evidence that a part is defective.

Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.

Reports by component

Ranked by how many owner reports name each component category

  • Electrical240.0%
  • Fuel system240.0%
  • Brakes120.0%

Percentages are of component mentions. A single complaint can name more than one component, so these do not sum to the total complaint count.

Each component in detail

What the reports in each category say, in the owners' own words

Electrical

Reports naming the electrical system — wiring, battery, charging, control modules, infotainment and electrical accessories.

2
reports

From owner reports, verbatim

The safety component that is covered under the SBC warranty is the entire brake master cylinder specifically the part that is bad is the brake pedal position sensor The car is undriveable without it, they have a 25-year warranty on it yet they have no parts and no way to fix it which is obviously unacceptable they've also refused to provide a loaner car until they come up with a way to fix my car leaving me on the side of the road with nothing to drive it's unacceptable! My safety and everybody's safety on the road is affected by this because the car won't stop if you drive it and you have really strong legs you can get it to slow down and eventually stop it's completely unsafe The brake pedal cannot tell the computer where it is in its travel which means the system doesn't know that you're applying the brakes which don't work. Yes the problem has been confirmed by two shops one of which has a snap-on scanner which I can attach the scan to showing the issue and currently the car is sitting at a shop that uses Mercedes-Benz only star system the same system that they use in the dealership there is no question at any level what is wrong with the vehicle. The car is not safe to drive to the dealership and now in the winter this $132,000 convertible isn't going to be driven in the salt just to get to a dealership to find out what they're not going to do for me I've already confirmed and share the scans and images and everybody I've spoken with at the dealerships agrees that it's ridiculous that Mercedes has a 25-year warranty on a part that they do not make do not have and cannot fix Yes there are two different brake malfunction lights that are on the dash you cannot clear them as though in a code way like you can on some things and the car is not to be driven, the problem first arose a couple months ago and we started diagnosing it until on the Facebook forum somebody told me that it's covered by a 25-year SBC warranty which when I contacted the dealer and Mercedes-

NHTSA ID 11702808 · filed Dec 3, 2025

Mercedes SL600 BCM has electrical issues leading to a fire it is available for inspection. The car can burn down in a garage putting me and all others in or near the dwelling at risk. Yes the problem has been confirmed independently. No BCM issues lead to red light on dash.

NHTSA ID 11557421 · filed Nov 29, 2023

Too few reports in this category for a page of its own — they appear in the full complaint list.

Fuel system

Reports naming fuel storage or delivery — tanks, pumps, lines, injectors and fuel leaks.

2
reports

From owner reports, verbatim

TL* THE CONTACT OWNS A 2004 MERCEDES BENZ SL600. THE CONTACT STATED THAT WHILE DRIVING 50 MPH, THE VEHICLE STALLED. THE VEHICLE WAS TAKEN TO A DEALER WHERE THE TECHNICIAN DIAGNOSED THAT THE FUEL TANK NEEDED TO BE REPLACED. THE VEHICLE WAS NOT REPAIRED. THE MANUFACTURER WAS MADE AWARE OF THE FAILURE. THE FAILURE MILEAGE WAS 40,000 AND THE CURRENT MILEAGE WAS 40,100.

NHTSA ID 10614504 · filed Jul 18, 2014

KNOCKING NOISE BEGIN TO APPEAR BEHIND THE DRIVER'S SEAT. AT FIRST, BELIEVED TO BE LOOSE ITEM IN THE TRUNK BUT CHECK AND CAN'T FIND. LOOKED AT FORUM AND FOUND THAT MANY 2003/2004 MERCEDES BENZ SL CLASS HAS THE SAME PROBLEM WITH DEFECTIVE GAS TANK BAFFLE. WHENEVER I BRAKE OR ACCELERATE, I HEAR THE KNOCKING NOISE, WHICH ALSO KNOCKS TWO OR THREE TIMES EVERYTIME I BRAKE OR ACCELERATE. IT SOUNDS LIKE SOMETHING IS HANGING FROM A STRING OR FLOATING AND THEN BECAUSE OF INERTIA IT KNOCKS AGAINST THE SIDE OF A CONTAINER. THE HAZARD THAT I FEAR IS THAT THE FLOATING MATERIAL IN THE GAS TANK KNOCKS AGAINST THE TANK AND CREATE A SPARK THAT CAN IGNITE THE TANK CAUSING A FIRE. THE KNOCKING NOISE HAPPENS EVERYTIME THE CAR JERKS FROM BRAKING OR ACCELERATING. *TR

NHTSA ID 10341914 · filed Jul 7, 2010

Too few reports in this category for a page of its own — they appear in the full complaint list.

Brakes

Reports naming service brakes, the antilock braking system, brake hoses, master cylinders or the parking brake.

1
report

From owner reports, verbatim

The safety component that is covered under the SBC warranty is the entire brake master cylinder specifically the part that is bad is the brake pedal position sensor The car is undriveable without it, they have a 25-year warranty on it yet they have no parts and no way to fix it which is obviously unacceptable they've also refused to provide a loaner car until they come up with a way to fix my car leaving me on the side of the road with nothing to drive it's unacceptable! My safety and everybody's safety on the road is affected by this because the car won't stop if you drive it and you have really strong legs you can get it to slow down and eventually stop it's completely unsafe The brake pedal cannot tell the computer where it is in its travel which means the system doesn't know that you're applying the brakes which don't work. Yes the problem has been confirmed by two shops one of which has a snap-on scanner which I can attach the scan to showing the issue and currently the car is sitting at a shop that uses Mercedes-Benz only star system the same system that they use in the dealership there is no question at any level what is wrong with the vehicle. The car is not safe to drive to the dealership and now in the winter this $132,000 convertible isn't going to be driven in the salt just to get to a dealership to find out what they're not going to do for me I've already confirmed and share the scans and images and everybody I've spoken with at the dealerships agrees that it's ridiculous that Mercedes has a 25-year warranty on a part that they do not make do not have and cannot fix Yes there are two different brake malfunction lights that are on the dash you cannot clear them as though in a code way like you can on some things and the car is not to be driven, the problem first arose a couple months ago and we started diagnosing it until on the Facebook forum somebody told me that it's covered by a 25-year SBC warranty which when I contacted the dealer and Mercedes-

NHTSA ID 11702808 · filed Dec 3, 2025

Too few reports in this category for a page of its own — they appear in the full complaint list.

Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.

Elsewhere on this vehicle

Data sources

Data on this page last refreshed .