Q&A

 Master

A short would bring the light on all the time as the switch provides a path to ground. Does the dome light work with the roof mounted dome light in the "door position" when the door is opened on the passenger front door? If not the problem is in the lamp fixture, pop off the transparent cover and check the contacts. Exercise the door switches in the door jambs and see if it then operates the light. Perhaps remove the screw holding the switch to the dor jamb and place the wire directly to ground se if the light then works which would confirm bad switch.