1994 Mercedes-Benz 420 Electrical system Problems
- Complaints
- 5about this part
- Share
- 31%of 16 total for the year
- Median mileage
- 128,298miles
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 5 complaints about the electrical system of the 1994 Mercedes-Benz 420, 31% of the 16 complaints for this model year. Where a mileage was given, the median is 128,298 miles.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“Vehicle is running erratically. Upon investigation, I found that the engine wiring harness in model years including my 1994 mercedes benz e420 have a chronic problem with deteriorating insulation. As some fires and crashes have been reported, I am paying to have this part replaced.”
NHTSA complaint #10220009, filed 2008-03, 139,595 miles“I own a 1994 s 420 Mercedes-Benz I am very concerned for my child's safety and my own safety as well. The wiring harness is shorting out everywhere... Shame on Mercedes-Benz of america..they know about this danger and just ignore the whole thing.. I've researched it really well and the same problem occurs over and over with all cars of this vintage..I wonder how many people will have to die before they recall on this dangerous situation???they should stand up to the plate.. The harness is 7-8 hundred dollars.. Come on guys!!! How much do you think your life is worth?? …”
NHTSA complaint #10225890, filed 2008-04, 90,000 miles“Car stopped shifting, check engine light and asr light appeared while driving. Took car into auto mechanic and was told wiring harness would need to be totally replaced and would cost more than auto's worth. Said these cars were notorious for having wiring harness problems and can not believe it has not caught on fire yet.”
NHTSA complaint #10452795, filed 2012-03, 170,000 miles“Vehicle checked and found that insulation on all of the fuel injection wiring, temperature sensor and fan thermal switch harness deteriorated causing wires to rub together. Consumer discovered that harness insulation is made of very poor material. The insulation breaks very easy at the touch and turns into dust. The whole wire harness is in the same situation this is a major safety issue can stall or shut off while driving at high speed. Replace of wire harness at a cost of$1500 was needed to fix.”
NHTSA complaint #10169170, filed 2006-09, 117,000 miles“5/18/2006. Check engine light appeared. Took vehicle to mbz repair shop and found the engine wiring harness's wire insulation breaking apart and exposing the bare wiring. Cost of repair +$900.00.”
NHTSA complaint #10157901, filed 2006-05Electrical system: other model years
Other parts of the 1994 Mercedes-Benz 420
4 complaintsOther or unknown
4 complaintsAir bags
1 complaintsEngine cooling
1 complaintsSeats
1 complaintsVehicle speed control
1 complaints
← All problems reported for the 1994 Mercedes-Benz 420
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Nov 1, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology