My dome light works fine using the ON switch. However, when it is in the DOOR position, with the doors closed, the passenger side light glows faintly. When either door is opened, both lights come on to full brightness as they should. I have taken the dome light apart and cleaned the contacts.

With the switch in the DOOR position, and the doors shut, my multimeter reads 4.7 volts from the chassis ground point to the ground point on the dome light.

If I just plug in the light, without screwing it in at the ground point, I do not get the passenger side light glowing dimly with the doors shut.

I have LED dome lights. I also have a hard wired radar detector that is connected to the "ignition" accessory terminal in the under-dash fusebox, and grounded to its main ground point.

 

Check the switch in the door. Maybe, it's beginning to fail. Or have some kinda hinky contact issue,

 

I think I have this figured out. The LED can illuminate with just the small fraction of current that's always present in the door switch circuit, whereas the stock incandescent bulb won't illuminate until the current reaches a certain level.

The solution is to use better quality LEDs with built in resistors or to wire a small resistor across the festoon bulb socket.

 

FWIW... the guy that put in my alarm device, replaced the OEM interior bulbs with Philips type, as gratis. Single LED source, not the multiple ones you see on EBay. They work fine.



http://www.amazon.com/Philips-129454...QPB1AMEG63P9EB