Hi everyone! I've got (what I think) a wierd thing where when I first start up my 1990 300D in the morning my indicator on the dashboard lights up that I have a lightbulb out. What seems wierd to me is that I don't have any lights on at the time and not sure why this should be on??

I have had a bit of problems at night with this light coming on and then going out and I'm 99% sure that I've got a taillight bulb that is flakey and causing that but would that also cause the indicator to show up during the day??

Thanks for all your help!! Mike

P.S. I have searched the archives but haven't been able to find anything of much help!

When the indicator lights went screwy in my 91 SE, it was due to overly worn voltage regulator brushes. More appropriately, a new voltage regulator fixed the problem. It was only a couple of days between the first warning lights and the engine stalling. Since your car is a Diesel, maybe it's not susceptible to stalling.

Did you check the manual for what would cause that light to come on? Maybe the system can check resistance without turning on the lights.

Sixto
91 300SE
81 300SD

i thought those systems worked by sensing a ground? in the tail lights, without the ground the light came on. Im probably wrong but that is my understanding, thus it would be on all the time. My dad's bimmer's indicator comes on w/out the lights being on if something is out.
R

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83 300SD.......sold
96 integra SE....sold
99 a4 quattro....sold
2001 IS300.......sold
2002 330i.........current.
2004 highlander limited....current.

The light always comes on when you switch the ignition on, but should go out when you start the car.

My mechanic nearly went nuts trying to fix an intermittant lamp out indicator on the 87 300SDL he eventually sold to my brother. HE found the problem quite by accident -- he was outside smoking a cigarette when his wife came home one night, and one of the license plate lamps was out, but came on when she drove over the lip of the garage. Lamp was bad, only worked intermittantly, and caused the lamp out light on the dash to come on and off. New bulb fixed it.

The lamp out indicator works by measuring relative current flow between the lamps in all the affected lighting circuits. Volvo uses a set of coils and Read magenetic switches, I have no idea what MB uses. However, it is important to match the bulbs, as American lamps don't have the same current draw as European lamps, ditto for old lamps vs new.

Peter

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1972 220D ?? miles
1988 300E 200,012
1987 300D Turbo killed 9/25/07, 275,000 miles
1985 Volvo 740 GLE Turobodiesel 218,000
1972 280 SE 4.5 165, 000 - It runs!

Mike,

I second psfred's experience with the rear license plate illumination lamps. It took quite a while to track that down mainly because I was not checking in the dark, and in daylight those lamps are pretty hard to notice unless you are looking up at them. I also think you may have a brake light out as you are probably stepping on the brake when you start the car or try to put it in gear, which should pick up a bad brake bulb. Good luck, and hope it helps. Jim

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Own:
1986 Euro 190E 2.3-16 (291,000 miles),
1998 E300D TurboDiesel, 231,000 miles -purchased with 45,000,
1988 300E 5-speed 252,000 miles,
1983 240D 4-speed, purchased w/136,000, now with 222,000 miles.
2009 ML320CDI Bluetec, 89,000 miles

Owned:
1971 220D (250,000 miles plus, sold to father-in-law),
1975 240D (245,000 miles - died of body rot),
1991 350SD (176,560 miles, weakest Benz I have owned),
1999 C230 Sport (45,400 miles),
1982 240D (321,000 miles, put to sleep)