I have a HUGE problem with a 2005 rx-8, a while ago I wanted to install a device right under the rear view mirror and the device needed a 12V power source. So instead of drawing the power from the cigarette lighter, I went ahead took the upper dome light (the one by the rear view mirror) off and I used the dome light power cable as my power source.

At the beginning, everything worked fine however one day after getting out of work. I noticed that there was a short circuit and the front dome light was burned and the wiring (for the upper ceiling) was burned too . I went ahead and retraced all the damage wiring and replaced it, while also replacing the dome light, so now all was good. However I noticed, the light (domes light, door light...) stayed on even if the door was closed. But it would flicker and sometime turns off and then turns on but the light looked like it had some voltage leak.

I have checked most of the wiring of the car (under door panel, under the driver panel....)

Do you guys know what could be wrong or any ideas such modules that I need to check?