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: 15 of 19 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 14 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
Engine. Review the 2 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
Engine And Engine Cooling. Review the 2 owner reports in this category and discuss these concerns during a pre-purchase inspection. Read reports →
NHTSA owner reports · September 18, 2026 snapshot.
0 crash reports1 fire reports0 injury reports
What owners actually said
19 reports
163,000 miles · Mar 24, 2016
Electrical SystemElectronic Stability Control (esc)Unknown Or Other
PARKED THE VEHICLE AND PLACED IT IN PARK THEN TURNED IGNITION OFF. BURNING SMELL COMING FROM VEHICLE THEN SMOKE STARTED GOING IN THROUGH VENTS AND SEEMED LIKED IT WAS COMING FROM UNDER THE CAR. THE ELECTRICAL WIRING HARNESS IS CREATING MASS AND THE CAR NEARLY WENT UP IN FLAMES. THE FIRE DEPARTMENT ARRIVED AND WERENT ABLE TO PUT …
Read full complaint
PARKED THE VEHICLE AND PLACED IT IN PARK THEN TURNED IGNITION OFF. BURNING SMELL COMING FROM VEHICLE THEN SMOKE STARTED GOING IN THROUGH VENTS AND SEEMED LIKED IT WAS COMING FROM UNDER THE CAR. THE ELECTRICAL WIRING HARNESS IS CREATING MASS AND THE CAR NEARLY WENT UP IN FLAMES. THE FIRE DEPARTMENT ARRIVED AND WERENT ABLE TO PUT OUT THE SMOKE AS THE SOURCE OF IT WAS NOT IMMEDIATLY DETERMINED. I AM NOT LOOKING AT THOUSANDS OF DOLLARS IN REPAIRS.
NHTSA ODI #10851497
180,000 miles · Mar 4, 2015
Engine
THE FUEL INJECTION ENGINE HARNESS WIRING HAS COMPLETELY DETERIORATED DUE TO THE USE OF A BIO DEGRADABLE MATERIAL BY MERCEDES BENZ. HAS RESULTED IN A LOT OF SHORTING ISSUES, WHICH RESULTED IN AIR CONDITIONING TURNING OFF, FAN CONTROL OFF, ENGINE HEATING UP, BLUE AND BLACK SMOKE, AND NOW SMOG FAILURE. THIS IS A KNOWN PROBLEM TO …
Read full complaint
THE FUEL INJECTION ENGINE HARNESS WIRING HAS COMPLETELY DETERIORATED DUE TO THE USE OF A BIO DEGRADABLE MATERIAL BY MERCEDES BENZ. HAS RESULTED IN A LOT OF SHORTING ISSUES, WHICH RESULTED IN AIR CONDITIONING TURNING OFF, FAN CONTROL OFF, ENGINE HEATING UP, BLUE AND BLACK SMOKE, AND NOW SMOG FAILURE. THIS IS A KNOWN PROBLEM TO MERCEDES AND THEY NEED TO FIX IT. I HAVE HAD OVER $4000 REPAIRS AND STILL NEED TO GET THE ENGINE HARNESS CHANGED, WHICH IS A CUSTOM PAR AND MERCEDES WILL TAKE 2 MONTHS TO BUILD AND THE REPAIR ESTIMATE ON MY CAR IS OVER $8000 BY MERCEDES STEVEN CREEK. THESE PROBLEMS GOT ME 2 TRAFFIC TICKETS FOR NO REASON. DISGUSTING. MERCEDES NEEDS TO RECALL AND FIX THIS ISSUE, AND PROVIDE EXCELLENT SAFETY AND CUSTOMER SERVICE, TO PEOPLE WHO BUY THEIR CAR. I REQUEST MBUSA PRESIDENT TO KINDLY LOOK INTO THIS MATTER. *TR
NHTSA ODI #10692130
Mileage unknown · Aug 4, 2014
Electrical SystemFire
WIRING CAUGHT FIRE DUE TO FAULTY WIRING HARNESS INSULATION, WHICH IS WELL DOCUMENTED. YET, MERCEDES REFUSES TO RESOLVE/RECALL THIS ISSUE. WIRING HARNESS NEEDS TO BE REPLACED. *TR
NHTSA ODI #10618874
278,000 miles · Nov 12, 2012
Electrical SystemEngineFuel/propulsion System
FAULTY WIRING IN ENGINE HARNESS RESULTED IN LOSS OF POWER AT SPEED ON A MAJOR INTERSTATE, LUCKILY AT THE TIME I WAS ABLE TO GET OFF THE ROAD SAFELY. IT WAS DETERMINED THAT THE CAR'S CHARGING SYSTEM HAD BEEN SHORTED OUT. STILL WAITING ON OTHER SYSTEM TESTS. THIS IS A KNOWN PROBLEM WITH CERTAIN MERCEDES. WHY ISN'T ANYTHING BEING D…
Read full complaint
FAULTY WIRING IN ENGINE HARNESS RESULTED IN LOSS OF POWER AT SPEED ON A MAJOR INTERSTATE, LUCKILY AT THE TIME I WAS ABLE TO GET OFF THE ROAD SAFELY. IT WAS DETERMINED THAT THE CAR'S CHARGING SYSTEM HAD BEEN SHORTED OUT. STILL WAITING ON OTHER SYSTEM TESTS. THIS IS A KNOWN PROBLEM WITH CERTAIN MERCEDES. WHY ISN'T ANYTHING BEING DONE ABOUT THIS? *TR
NHTSA ODI #10484072
100,000 miles · Feb 13, 2010
Electrical System
I OWN A 1993 400E MERCEDES. RECENTLY IT HAS HAD MAJOR DIFFICULTY TURNING OVER. I TOOK IT TO MY LOCAL MERCEDES BENZ REPAIR SHOP. THEY TOLD ME IT THE ENGINE HARNESS HAS GONE BAD AND NEEDS TO BE REPLACED COMPLETELY. EVIDENTLY THIS IS A VERY COMMON PROBLEM WITH THIS VEHICLE AS MERCEDES USED SUB-STANDARD MATERIALS WHEN BUILDING THE …
Read full complaint
I OWN A 1993 400E MERCEDES. RECENTLY IT HAS HAD MAJOR DIFFICULTY TURNING OVER. I TOOK IT TO MY LOCAL MERCEDES BENZ REPAIR SHOP. THEY TOLD ME IT THE ENGINE HARNESS HAS GONE BAD AND NEEDS TO BE REPLACED COMPLETELY. EVIDENTLY THIS IS A VERY COMMON PROBLEM WITH THIS VEHICLE AS MERCEDES USED SUB-STANDARD MATERIALS WHEN BUILDING THE WIRING HARNESS. THIS CAUSES MAJOR SAFETY ISSUES AND I BELIEVE MERCEDES SHOULD BE FORCED TO BEGIN RECALLING THESE VEHICLES. *TR
NHTSA ODI #10310130
211,000 miles · Feb 2, 2009
Electrical System
WIRING HARNESS ON MERCEDES BENZ 400E FAILED AND ENTERED A LOW POWER BACKUP MODE ON THE HIGHWAY FAR AWAY FROM OUR RESIDENCE. WIRING HARNESS IS CHARRED AND HARNESS SHORTED OUT ON ENGINE. *TR
NHTSA ODI #10257260
210,789 miles · Aug 2, 2008
Electrical System
MERCEDES 400 E HAS A TERRIBLE WIRE HARNESS DRY ROTTED FROM TEMPERATURE FROM ENGINE. *TR
NHTSA ODI #10236751
Mileage unknown · Jan 10, 2007
Electrical System
THE WIRE HARNESS IS CRACKED AND ROTTEN. THE MOTOR DOES NOT RUN RIGHT. IT STALLS AND CUTS OUT. THE MECHANIC SAYS TO JUST GIVE HIM $1000.00 FOR A TEMP. FIX DUE TO THE MATERIALS USED IN THE REPLACEMENT HARNESS. *JB
NHTSA ODI #10178341
160,000 miles · Dec 22, 2006
Engine And Engine Cooling
TL* - THE CONTACT'S 1993 MERCEDES BENZ, 400E WITH THE CRUISE CONTROL SET INCREASED THE VEHICLE INCREASED SPEED. THE CONTACT IMMEDIATELY DROVE THE VEHICLE OFF THE HIGHWAY, THE VEHICLE WOULD NOT RESTART. THE CONTACT'S CAR WAS TOWED TO THE REPAIR SHOP. THE MECHANIC EXPLAINED THE FOLLOWING DETAILS TO THE CONTACT: THE AIR CLEANER W…
Read full complaint
TL* - THE CONTACT'S 1993 MERCEDES BENZ, 400E WITH THE CRUISE CONTROL SET INCREASED THE VEHICLE INCREASED SPEED. THE CONTACT IMMEDIATELY DROVE THE VEHICLE OFF THE HIGHWAY, THE VEHICLE WOULD NOT RESTART. THE CONTACT'S CAR WAS TOWED TO THE REPAIR SHOP. THE MECHANIC EXPLAINED THE FOLLOWING DETAILS TO THE CONTACT: THE AIR CLEANER WAS REMOVED WHICH INDICATED THE WIRING WAS DESTROYED AND THAT THIS IS TYPICAL FOR THIS VEHICLE INCLUDING A VERY HIGH FAILURE RATE OF THE WIRING HARNESS. THIS FAILURE, PER THE MECHANIC, CAN ALSO CAUSE A FIRE.
NHTSA ODI #10176827
160,000 miles · Dec 21, 2006
Vehicle Speed Control
DRIVING ON RT 101. SUDDENLY COULD NOT CONTROL ACCELERATION. NEARLY HAD AN ACCIDENT FORCING ANOTHER CAR OFF THE ROAD. TOOK THE CAR TO GERMAN MOTORS-MERCEDES REPAIR AND THEY INDICATED THAT THE ENGINE WIRING HARNESS WAS FALLING APART AND THAT THIS WAS A COMMON PROBLEM FOR THIS MODEL CAR. *NM
HIGH AMBIENT ENGINE COMPARTMENT TEMPERATURES ARE EXPERIENCED AFTER THE VEHICLE IS OPERATED AND THEN PARKED. IF THE VEHICLE IS RESTARTED A SHORT TIME LATER AND THE CHARCOAL CANISTER IS SATURATED WITH FUEL, IT IS POSSIBLE THAT FUEL VAPOR MAY BE EXPELLED THROUGH THE INLET VENT LINE OF THE CANISTER ONTO THE ELECTRIC AUXILIARY RADIATOR FAN PRERESISTOR.
Consequence & remedy
Consequence: UNDER CERTAIN OPERATING CONDITIONS THE ELECTRIC AUXILIARY RADIATOR FAN PRERESISTOR BECOMES HOT ENOUGH TO IGNITE THE FUEL EXPELLED FROM THE CHARCOAL CANNISTER AND RESULT IN AN UNDERHOOD FIRE.
Remedy: DEALERS WILL REPOSITION THE FUEL VAPOR CANISTER VENT LINE AWAY FROM THE ELECTRIC FAN PRERESISTOR. IN ADDITION, THE PRERESISTOR WILL HAVE A LARGER HEAT SHIELD AND A FUSED WIRING HARNESS WILL BE INSTALLED.
Model-level recall history does not show whether a particular VIN is affected or has received a repair. Check a VIN with NHTSA ↗
NHTSA investigations
0
No exact-year investigations in this snapshot.
1993 Mercedes Benz 400E Problems, Complaints & Recalls | Skip That Year