Hello! I recently got a 1993 Ranger XLT with a 4.0 V6. I've been fixing some little odds and ends in the interior and noticed the passenger side bulb was missing on the overhead dome light. I went and got a replacement and then put it in and it automatically lit up, even though I hadn't turned it on. I guess it must be shorting to power somewhere? Does anyone else have this issue or have some probable causes?
Thanks!

 

Map reading light? Is there a switch up on the dome light?

 

Map light will have switch on its housing

Dome light is powered by a door jamb switch, plunger type, or can be turned on manually by rotating Head light switch, dimmer, all the way clockwise, this will also turn on Cargo light above the bed if so equipped

 

There is a switch on the dome light. With the doors closed and all the other lights off, I flipped the dome light switch to all the positions and it still wouldn't turn off

 

Is there only ONE lamp in the light? If so, the door sensor switch is broken. Someone removed the lamp to keep it from burning all the time.

 

This is whats confusing "....noticed the passenger side bulb was missing...."

This would indicate there is more that one Dome Light bulb?
And that would be because there are Map lights

So Dome light in the center and two Map light bulbs, like this housing: https://images.fobbattery.com/storag...3524905329.jpg

If one of the side bulbs is not going off with switch control then the switch is bad in the housing, pull housing off, take a picture of wiring, then disconnect wires and check switch function

There should be 3 wires, one with full time 12volts(maps), then one with 12v ONLY when a door is open(dome), and a ground wire

There might be a 4th wire that runs to Cargo light from dome light