Dome Light Mystery
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Dome Light Mystery
My 2008 F150, 5.4L V8 Triton, has been having a consistent annoyance with the dome light turning on and off. This can happen when I am driving or shortly after I turn the truck off. I have already replaced the door switch on the driver’s side as well as replaced the light-dimmer combo switch. I had a suspicion that it might have been the pigtail but now I am unsure, let me explain further. This problem is most annoying within the first 30 minutes or so of driving, or if I am driving over a bumpy road the dome light will turn on. My current fix has been to tap the area with the palm of my hand underneath the light-dimmer combo switch. Another odd occurrence with this is that the display on the stock radio will dim, yet it will not go out completely, but it will dim to the point that thepassenger side of the display cannot be read and I can still see the driverside of the display even though it is fairly dim.
As I said, I did not replace the pigtail yet, and I really do not think it is the pigtail as I have had the dome light come on while the light-dimmer combo was unplugged (my tapping wasn’t working, so I pried the switch off and unplugged the switch to no avail). I have had one of the wires on the light-dimmer switch (pigtail side) break (probably due to me constantly jarring the connections with the palm of my hand), it controlled the back light for the dashboard, but this has already been fixed. I have been leading towards a bad ground somewhere located by the light-dimmer switch because the problem seems to occur earlier when driving or shortly after turning the truck off (this could be do to temperature change), it will happenon bumpy roads (altering the ground contact due to uneven vibration), I am able to “turn off” the dome light by forcefully tapping below the switch, and finally this occurrence seems to be effecting my radio display, perhaps due to a bad common ground or ground fault effecting the radio wiring…? Any thoughts on this would be greatly appreciated!
As I said, I did not replace the pigtail yet, and I really do not think it is the pigtail as I have had the dome light come on while the light-dimmer combo was unplugged (my tapping wasn’t working, so I pried the switch off and unplugged the switch to no avail). I have had one of the wires on the light-dimmer switch (pigtail side) break (probably due to me constantly jarring the connections with the palm of my hand), it controlled the back light for the dashboard, but this has already been fixed. I have been leading towards a bad ground somewhere located by the light-dimmer switch because the problem seems to occur earlier when driving or shortly after turning the truck off (this could be do to temperature change), it will happenon bumpy roads (altering the ground contact due to uneven vibration), I am able to “turn off” the dome light by forcefully tapping below the switch, and finally this occurrence seems to be effecting my radio display, perhaps due to a bad common ground or ground fault effecting the radio wiring…? Any thoughts on this would be greatly appreciated!
Last edited by mrc1503; Dec 24, 2014 at 08:36 AM.
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From: Lake Mary Florida
There are also some here as a sticky ("Useful" thread). Here's a link to the wiring diagrams that have been posted on it:
https://www.f150forum.com/f4/wiring-diagrams-41510/
https://www.f150forum.com/f4/wiring-diagrams-41510/
