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Truck was sitting in the parking lot at work and had been sitting there for several hours. I watch cameras as part of my job and so I typically park the truck in the lot where there is a clear view from multiple sides. I happen to glance over and notice that the running lights are on. I didn't have the lights on at all before I parked it for the evening. I reviewed some footage and the lights popped on by themselves a few minutes before I noticed. Not the headlights just the running. I went out and checked the switch and it was most definitely pushed all the way in. That switch is also brand new.
Truck has never done this to my knowledge before. Any ideas of why this happened? Fuses (which are also new)? Grounds?
Probably a bad "new" switch. First time I've heard of your particular problem, but having bad electrical components right out of the box is rampant. Having them fail a week or two into their service is even more common than having them bad right out of the box.
A fuse being bad can't cause electricity to flow no matter how it's bad. The power is coming from somewhere before it gets to the fuse. So wherever that source is, or the wiring in-between, is your problem.
I suspect the new switch. But what was the reason for changing it out in the first place? Other problems cropping up?
Probably a bad "new" switch. First time I've heard of your particular problem, but having bad electrical components right out of the box is rampant. Having them fail a week or two into their service is even more common than having them bad right out of the box.
A fuse being bad can't cause electricity to flow no matter how it's bad. The power is coming from somewhere before it gets to the fuse. So wherever that source is, or the wiring in-between, is your problem.
I suspect the new switch. But what was the reason for changing it out in the first place? Other problems cropping up?
Paul
I had been chasing a dash light problem and decided to replace all the common causes. So new switch, fuses, LED bulbs, etc. With the hours I work(graveyard 12 hour shifts) I havent needed the lights at all before until the recent change in weather.
Try jiggling the switch while it's in the Off position, and see if you can get it to duplicate the fault. A dark garage will work, as will a mirror in front of the truck showing you the lights, but if you could wire in a buzzer that might be better for detecting a short few milliseconds of current flow.
Did you notice if the gauge lights were on too? I think they'd almost have to have been on.
Originally Posted by 1TonBasecamp
The power is coming from somewhere before it gets to the fuse. So wherever that source is, or the wiring in-between, is your problem.
If it's a phantom positive voltage problem, then the current could be coming from either side of the fuse - but it could be coming from outside the light switch. Or am I reading that wrong?
I think it's the switch too.
Yes, from the switch, or from outside the switch. Just not the fuses themselves was what I was saying. As they're just in the middle of the circuit, nothing is coming from them. So replacing them would not change anything.
In theory at least...
And Stangman, if you have other lights work but the dash lights still don't, you might try reversing the bulbs. Some LED's (all of them?) are polarity sensitive and will only work when inserted one way. Be nice if the manufacturers would make this plain and clear to purchasers.
And I should talk, as many of our products seem so intuitive that we neglect to even include instructions! Well not everyone has worked on these trucks for 40 years as it turns out, so yeah, instructions would be nice sometimes!
And by your username it sounds like you've been around old vehicles for awhile now at least? So you know that the dash lights are all controlled through the rheostat section of the light switch so you have to turn the **** to make them brighter?
Figured I'd add that just in case, since it's come up literally three times on different forums just in the last month or so. Worth checking at least.