If I understand your post, the light is on even when no exterior lights are being used. The light should only come on when you select a function where the bulb is burnt out. For example if a directional light is out, the dash light will come on only when you use that signal. I have the exact same problem in my wife's 89 300CE. It comes on as soon as the car is started and stays on til the car is shut off. It's been on a few months now, because I haven't had time to fool with it. I will trade cars with her tomorrow and check it out. I suspect a module, but I'll let you know. By the way she's had all kinds of MBs, but she loves that little coupe even over the SELs. We drove it to Vegas a couple of weeks ago. I let it stretch it's legs at 80 to 100 MPH during some long straight stretches through the Mahave Desert and Dealth Valley with no bears around. That M103 really performs.
