1990 300e intermittent Driver's door sensor
 

Now that I've slowly but surely solved issues with my son's college car, it's time to tackle this nagging problem that we've had from the day we bought the car 6 months go. (I even have this issue with my '91 300sl- still on my to-do list).

When I open the driver's door to get in, the interior light doesn't come on. All the other doors turn their respective interior lights on. I've already swapped door plunger sensors with the passenger side, but still the same issue.

I'm thinking this is a common fault. Because of the number of times that the driver's door is opened, some part must be in need of repair.

What is the cause and how do I fix this?

Thanks.

I'm guessing there's a broken wire in the area where the wiring harness exits the door and enters the A-pillar

MILS, makes sense to me. I'll check it out and report back next week. thanks.