My Dome Light Won't Shut Off
by John WalkerDome lights inside of a vehicle operate through multiple switches. The standard control is located on an adjustable knob on the dashboard, typically to the left of the steering wheel, or on the headlight switch. Additional switches are mounted to each door and, on some vehicles, the trunk. Some modern vehicles mount a timed switch in the ignition switch. The light is controlled by a fuse that typically covers multiple items. A dome light that will not turn off means one of the switches is stuck in the "On" position.
Step 1
Adjust the dome light switch. Every vehicle has one. Some vehicles include a switch on the light, and one on the dashboard. The switch that controls the brightness of your dashboard display also can turn on the dome light, when the switch is at its highest setting. Turn the switch to the lowest setting to see if the light turns off. You have a bad control switch if adjusting the knob does not dim the dashboard display at all.
Step 2
Open each door and locate the door switch. Look for a switch stuck in the open position. Manually press each switch to see if the light will deactivate. You should feel each one click. Excessive play or no clicking sound indicates a faulty switch.
Step 3
Start the vehicle and allow it to run for five minutes. Turn the key off and remove it from the ignition. Open and shut each door. The light should turn off within five minutes of all doors being closed.
Step 4
Trace the wiring for each switch. You will want to take the vehicle to a mechanic to have the wiring traced, as the location of the wiring will run from each door into the frame of the vehicle and terminate at the wiring harness behind the dash. The lines will be crossed at a junction point in one of the wiring harnesses for the lights, if all of the switches are fully operational.
Step 5
Remove the bulb to avoid draining the battery until the wiring can be inspected by a mechanic. You can try removing the fuse, but the fuse likely controls multiple interior systems, and so you may not want to remove it.
References
- "Haynes Repair Manual: Mazda 626 & MX-6 Ford Probe"; Jay Storer and John Haynes; 2001
- "Chilton Ford Pickups 1965 - 86"; Nick D'Andrea, 1986
Tips
- The likely cause of a dome light not turning off is either the dashboard light control knob being activated accidentally or a broken door switch. You can remove the wire from the door switch, if you are able to access the backside of the switch. The wire pulls off of the switch easily. Replacement of any of the switches requires unscrewing the retaining screws, disconnecting the wiring harness and installing a new switch. The only difficult part is accessing the back of the switch where the retaining screws are located.
