Almost all the interior lights on my 1990 300E don't work. One day (about 2 months ago) I turned on the headlamps and none of the interior lights went on.

I checked the fuses and they seem fine. I also tried fiddling with the knob that dims the dash.

THE following DO NOT light on:

The dash lights (speedometer, tach, and other guages), all the front vents, all the climate control buttons, the radio lights, the window switches by the shifter, (the shifter light burned out 2 years ago, so I don't know about that one, but I suspect that would be out too), and the rear window switches, the sunroof switch, and the headlight switch lights.

The following interior lights DO go on:

the Front dome (when you open the door and when you turn it on manually), the rear light for the back seats , the lights in the bottom of all 4 doors when you open them, the vanity mirror lights for both the passenger and driver, and the glove box light.

Note: when you start the car, all the warning lights come on (ie, SRS, washer light, oil light, check engine light etc.).

What could it be? Any suggestions? I'm tired of driving in the dark, and feels like I'm driving a clunker. I don't really feel like going to MB and paying $200 - $300+ which is money I really can't afford to give (and which I did too much in the past). thanks in advance.

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'90 300E
Lowered with Eibach Springs
Mouldings and bumpers painted body color
Clear front corners
94/95 W124 Taillights