The problem has been going on for years.

First symptom upon starting the lamp defective message would come on. Upon very careful inspection ALL bulbs are lit! When I press the "R" button I would get the temperature , mileage and clock back and the Lamp Defective message would not return, even after hours of driving. Upon restarting the car everything would be normal the Lamp Defective would not be lit.

Recently the Lamp Defective always comes on at a start. All bulbs are lit and have been replaced numerous times the license plate bulbs light work and have not been replaced.

Now the Lamp Defective light comes on at start and after hitting the "R" button the Lamp Defective will go out and come back on sometimes within a second or two, always within a minute or two. The Lamp Defective will come on while driving without touching the brake, turn signals or anything. It comes on simply while driving. It appears to be vibration oriented?? It will come on while sitting at a stoplight for several seconds. It does not come on upon initial brake application but sever, even 15 to 20 seconds later but not always.

The rear driving lights have the dreaded melted plastic and I have tried the bending and tinfoil fix and finally hard wired a bulb base into the taillight so I am confident they are making good contact.

I have read somewhere that there is a cold soldered joint in the headlight light switch. It is a pucker job, but I removed the switch opened it up and re soldered the obvious connections. Good news in that I didn't screw anything up. Bad news in that it fixed nothing!

Is it time to replace the headlight switch? Are salvaged switches OK? My bad in that I did not record a part number for the light switch.

Ideas please.

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1999 Mercedes E300TD daily driver sold at 238K miles 106K miles were mine, rust worm got it :-(
2006 Mercedes CDI new daily driver! 56,000 miles May 2016 now 85,625 Apr 2018 and Apr 2019 101,000 miles Apr 2020 109,875. March 2024 135,250, Dec 2024 145,000 miles