ENGINE COMPARTMENT FIRE NEAR DRIVERS FIREWALL. FIRE WAS EXTINGUISHED HOWEVER STRONG FUEL VAPORS REMAINED. ORIGIN OF FIRE UNKNOWN. I SUBMITTED A REPORT FOR MY 1999 MERCEDES WHICH CAUGHT FIRE FROM THE HOOD INSULATION FALLING ONTO THE HOT MANIFOLD IN THE SAME GENERAL AREA.
1994 Mercedes Benz SL500
Owner reports · Recalls · Investigations
Limited comparison data
There is not enough comparable history to draw a useful model-year comparison.
Counts are not adjusted for sales, age, mileage exposure or reporting. A lower count does not establish that a car is problem-free.
About this comparison →Model-year median: 6
0Recall campaignsView recall details →
0InvestigationsView investigation details →
Check a VIN with NHTSA ↗ Model-level counts do not show whether a particular VIN is affected or repaired.
Inspection summary
1994 Mercedes Benz SL500
NHTSA snapshot: September 18, 2026. 8 owner complaints · 0 recall campaigns · 0 investigations.
Counts are not failure probabilities and are not adjusted for sales, age, mileage exposure or reporting. One report may name several categories. Comparison method and limitations.
Top reported categories (up to 5)
- Electrical System: 8 reports
- Fuel/propulsion System: 1 reports
- Structure: 1 reports
Full reported-category list and vehicle report
Recall links
No recall campaigns in this snapshot.
Check a VIN with NHTSA. Model-level history does not establish whether a particular VIN is affected or repaired.
Print the top reported categories, recall links, snapshot date and comparison limits.
How this year compares
Owner complaints by model year
Compare all SL500 years →Counts vary with age, sales, mileage exposure and reporting. They are not failure rates.
What owners reported most
Tap a category to read its complaints. One report may name several components.
When problems were reported
Mileage at the reported incident
Limited mileage data: 7 of 8 reports include usable mileage. There isn’t enough coverage to show a useful chart.
NHTSA’s mileage field refers to the reported incident, not necessarily the filing date. This shows report counts, not the likelihood of a failure.
What to inspect
Issues worth paying extra attention to based on owner reports.
- Electrical System. Review the 8 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Fuel/propulsion System. Review the 1 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
- Structure. Review the 1 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
What owners actually said
8 reportsFACTORY MATERIAL DEFECT. ENGINE WIRE HARNESS INSULATION IS BREAKING DOWN AND FLAKING OFF, LEAVING EXPOSED WIRE. IGNITION IS POOR AND THREATENS TO STALL, ESPECIALLY WHEN ENGINE TEMPERATURE WARMS UP TO 85-90C. I FEAR THE ENGINE MAY FAIL OR CATCH FIRE DURING A DRIVE AND CAUSE AN ACCIDENT. THERE IS ALSO A SHORT IN THE AUDIO SYST…
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FACTORY MATERIAL DEFECT. ENGINE WIRE HARNESS INSULATION IS BREAKING DOWN AND FLAKING OFF, LEAVING EXPOSED WIRE. IGNITION IS POOR AND THREATENS TO STALL, ESPECIALLY WHEN ENGINE TEMPERATURE WARMS UP TO 85-90C. I FEAR THE ENGINE MAY FAIL OR CATCH FIRE DURING A DRIVE AND CAUSE AN ACCIDENT. THERE IS ALSO A SHORT IN THE AUDIO SYSTEM. THE VEHICLE IS BEAUTIFUL. IT IS A SHAME TO HAVE IT SITTING SINCE 2008. *TR
STARTED THE CAR AT WORK AND IT WAS RUNNING ROUGH HAD NO ACCELERATION. WENT INTO LIMP HOME MODE AND I WAS ABLE TO GET HOME. A MECHANIC FOUND THE WIRING HARNESS WAS DETERIORATING, FLAKING AND FALLING APART EXPOSING ALL THE WIRES. THE CAR WOULD NO LONG EVEN START. I CALLED MERCEDES TO SEE IF THEY WOULD HELP WITH THE COST OF THE PAR…
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STARTED THE CAR AT WORK AND IT WAS RUNNING ROUGH HAD NO ACCELERATION. WENT INTO LIMP HOME MODE AND I WAS ABLE TO GET HOME. A MECHANIC FOUND THE WIRING HARNESS WAS DETERIORATING, FLAKING AND FALLING APART EXPOSING ALL THE WIRES. THE CAR WOULD NO LONG EVEN START. I CALLED MERCEDES TO SEE IF THEY WOULD HELP WITH THE COST OF THE PART REPLACEMENT. THEY DENIED ANY PROBLEM WITH THE PRODUCT AND WOULD NOT ASSIST IN ANY REPAIR. I LOGGED A COMPLAINT WITH THEM UNDER MY NAME AND HAVE TRIED MANY TIMES TO GET ASSISTANCE WITH THE REPAIR. THE CAR IS STILL SITTING IN MY DRIVEWAY AS THE REPLACEMENT HARNESS IS OVER A $1000. *TR
WHILE ATTEMPTING TO TRACK DOWN THE CAUSE OF AN OCCASIONALLY ERRATIC IDLE I REMOVED THE ENGINE COVER TO EXAMINE THE PLUG WIRES AND DISCOVERED A RATHER ALARMING PROBLEM/SAFETY ISSUE. THE MAIN ENGINE WIRE HARNESS FOR THE FUEL INJECTORS AND OTHER ENGINE SYSTEMS HAD BARE WIRES!!?? UPON FURTHER EXAMINATION THE WIRE INSULATION …
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WHILE ATTEMPTING TO TRACK DOWN THE CAUSE OF AN OCCASIONALLY ERRATIC IDLE I REMOVED THE ENGINE COVER TO EXAMINE THE PLUG WIRES AND DISCOVERED A RATHER ALARMING PROBLEM/SAFETY ISSUE. THE MAIN ENGINE WIRE HARNESS FOR THE FUEL INJECTORS AND OTHER ENGINE SYSTEMS HAD BARE WIRES!!?? UPON FURTHER EXAMINATION THE WIRE INSULATION APPEARS TO HAVE SIMPLE VANISHED??? NOT JUST ON EXPOSED WIRES (AS COULD HAVE BEEN CAUSED BY RODENTS FOR EXAMPLE) BUT IF YOU PEAL BACK THE OUTER HARNESS COVER ALL THE WIRES INSIDE ARE BARE AND THERE APPEARS TO BE THE REMNANTS OF THE INSULATION AS POWDER WITH OCCASIONAL LITTLE PIECES OF VARIOUS COLORED INSULATION WITH CRACKS??? IN ALL MY YEARS OF MAINTAINING MY OWN VEHICLES AND HAVING OWNED IN EXCESS OF 30 AUTOMOBILES BOTH FOREIGN AND DOMESTIC I HAVE NEVER SEEN SUCH A PROBLEM. MY QUESTION FOR YOU IS, IS THIS NORMAL FOR A MERCEDES CAR THAT COST NEARLY $100,000 WHEN NEW? IS THIS A DESIGN DEFECT COVERED BY RECALL OR EXTENDED WARRANTY? MY LOCAL DEALER SAID IT WAS A COMMON PROBLEM BUT THAT THEY KNOW OF NO RECALL AND ESTIMATED THEY COULD REPAIR FOR ABOUT $1,600.00. IS IT SAFE TO DRIVE THE CAR? IS IT SAFE TO CONTINUE TO PARK THE CAR IN MY BASEMENT GARAGE? IS THIS A FIRE HAZARD OR ARE ALL SYSTEMS OFF WHEN PARKED? *TR
1994 MERCEDES BENZ SL500 ENGINE WIRING HARNESS FAILURE. HARNESS INSULATION SEEMS TO BE DISINTEGRATING. *JB
DT*: THE CONTACT STATED WHILE STOPPED AT A STOP SIGN, THE ENGINE STARTED MAKING LOUD NOISES. THERE WERE NO WARNING LIGHTS ILLUMINATED. THE VEHICLE WAS TAKEN TO THE DEALERSHIP, WHO DETERMINED THE ENGINE WIRING HARNESSES HAD TO BE REPLACED AND THAT THE VEHICLE WAS NOT SAFE TO OPERATE WITH SUCH WIRING CONDITIONS. THE REPAIR WAS …
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DT*: THE CONTACT STATED WHILE STOPPED AT A STOP SIGN, THE ENGINE STARTED MAKING LOUD NOISES. THERE WERE NO WARNING LIGHTS ILLUMINATED. THE VEHICLE WAS TAKEN TO THE DEALERSHIP, WHO DETERMINED THE ENGINE WIRING HARNESSES HAD TO BE REPLACED AND THAT THE VEHICLE WAS NOT SAFE TO OPERATE WITH SUCH WIRING CONDITIONS. THE REPAIR WAS RATHER EXPENSIVE AND WAS COVERED AT THE CONTACT'S EXPENSE. THE CONTACT ENCOUNTERED SEVERAL COMPLAINTS ON THE INTERNET FOR THE SAME DEFECT HOWEVER; NO RECALL HAD BEEN CONDUCTED YET. THE VEHICLE REMAINED AT THE DEALERSHIP.
MY WIRING HARNESS HAS DISINTEGRATED. I HAVE SHORTS IN THE WIRING THAT HAVE SO FAR AFFECTED THE ALTERNATOR, HEATING COOLING, FUEL INJECTION AND LIGHTS. *NM
HFM & OTHER WIRING HARNESSES ARE DETERIORATED. VEHICLE HAS BEEN MAINTAINED TO MANUFACTURERS RECOMMENDATIONS SINCE NEW. DETERIORATED WIRING HARNESS CAUSES CHECK ENGINE LIGHTS, IGNITION MALFUNCTIONS, ELECTRICAL SHORTS OCCUR IN THE ENGINE COMPARTMENT. WIRE INSULATION / COATINGS ARE OBVIOUSLY NOT UP TO THE TASK. THIS IS DANGEROUS S…
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HFM & OTHER WIRING HARNESSES ARE DETERIORATED. VEHICLE HAS BEEN MAINTAINED TO MANUFACTURERS RECOMMENDATIONS SINCE NEW. DETERIORATED WIRING HARNESS CAUSES CHECK ENGINE LIGHTS, IGNITION MALFUNCTIONS, ELECTRICAL SHORTS OCCUR IN THE ENGINE COMPARTMENT. WIRE INSULATION / COATINGS ARE OBVIOUSLY NOT UP TO THE TASK. THIS IS DANGEROUS SITUATION. *JB
Recall campaigns
0No recalls in this snapshot.
Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗
Defect investigations
0No exact-year investigations in this snapshot.
An investigation is not a finding of a defect, and closure does not prove a vehicle is problem-free.
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