Mercedes-Benz 420 Problems by Model Year
NHTSA recorded 64 consumer complaints across the 5 model years of the Mercedes-Benz 420 (1986–1999) that have at least 5 complaints. 1997 has the most, with 22. Across all years, the part named most often is electrical system (13 mentions). Pick a model year below to see its parts, mileage, recalls and service bulletins.
All 420 model years
Years with fewer than 5 complaints are not listed. The score compares years of the same model, allowing for the era and for how long each year has collected complaints: 50 is a typical year, lower means fewer complaints. It is not adjusted for sales volume.
| Year | Complaints | Median mi | Recalls | TSBs | Score (50 = typical) | Trend |
|---|---|---|---|---|---|---|
| 1999 | 5 | — | 0 | 0 | — | Not enough data |
| 1997 | 22 | 131,500 | 0 | 0 | — | Stable |
| 1995 | 15 | 95,784 | 0 | 0 | — | Stable |
| 1994 | 16 | 110,125 | 0 | 0 | — | Stable |
| 1986 | 6 | — | 0 | 0 | — | Not enough data |
Parts named most often, all years
Counts add up complaint mentions across the listed years. A complaint can name several parts.
- Electrical system13 25%
- Suspension12 23%
- Transmission and drivetrain6 11%
- Brakes6 11%
- Other or unknown5 9.4%
- Vehicle speed control4 7.5%
- Fuel system4 7.5%
- Visibility (wipers, defrost, mirrors)3 5.7%
Example complaints
One per model year, chosen for length and detail. Personal details are removed. They are consumer reports, not findings.
1995: “The engine wiring harness on my 1995 mercedes benz s420 has disintegrated. The wiring insulation is cracked and broken in many places, which has resulted in a non-operating condition. The car has stalled 3 times so far, in traffic, and will now not run at all. Apparently the wires have broken down due to the heat of the engine compartment. I believe the wires were not suitable for the application they were used for.”
NHTSA complaint #10453897, filed 2012-04, 91,567 miles1994: “I got 94 e420 benz with defect engine wiring harness. They are cracking. The idle is rough and I got engine code errors. One time the engine failed on the surface street. It was lucky there was no car behind me at that time. My mechanic told me that all mercedes models from 91-96 have this problem. That was so sad that no one has taken action against the factory.”
NHTSA complaint #10189151, filed 2007-04, 65,000 miles1997: “I am a victim of a dangerous safety design flaw in my 1997 mercedes benz e420. Last week, my wife was driving the car in a straight line on a local street near our home, when the passenger side coil spring flew out of the car, resulting in her completely losing control of the vehicle. There were no warning signs - no sounds, rattles, etc. Luckily, she was driving at a slow speed of 35mph and that the cars around her stopped, allowing her to maneuver the car to the shoulder of the road. As a result, she avoided any accident and was not hurt. …”
NHTSA complaint #10413904, filed 2011-07, 200,150 milesOther Mercedes-Benz models
3,963 complaintsMercedes-Benz E350
2,215 complaintsMercedes-Benz E320
1,164 complaintsMercedes-Benz ML350
952 complaintsMercedes-Benz GLK350
901 complaintsMercedes-Benz ML320
740 complaintsMercedes-Benz C250
725 complaintsMercedes-Benz GLC 300
657 complaints
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 27, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate. Methodology