Blinkers again...
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Elder User
Joined: Apr 2009
Posts: 922
Likes: 1
From: San Diego
Blinkers again...
Strange problem came up that doesn't quite match other issues with blinkers.
The blinkers work fine without the running/headlights on. (Although slowly with the truck not running).
Once I turn the lights on, the passenger side blinkers stop working, the lights come on and stay on without blinking. drivers side works fine.
I'm thinking the flasher maybe?
Before it happened:
I was checking out my trailer connection to make sure it wasn't all corroded or shorting. And I installed a missing bulb in the front pass side marker.
After it happened:
I replaced all of the sockets and lenses in the back, to brighten up things and fix issues with the backup lights which all work fine now.
I will pull that bulb out of the marker to see if it caused it but I am kinda puzzled.
The blinkers work fine without the running/headlights on. (Although slowly with the truck not running).
Once I turn the lights on, the passenger side blinkers stop working, the lights come on and stay on without blinking. drivers side works fine.
I'm thinking the flasher maybe?
Before it happened:
I was checking out my trailer connection to make sure it wasn't all corroded or shorting. And I installed a missing bulb in the front pass side marker.
After it happened:
I replaced all of the sockets and lenses in the back, to brighten up things and fix issues with the backup lights which all work fine now.
I will pull that bulb out of the marker to see if it caused it but I am kinda puzzled.
Elder User
Joined: Nov 2004
Posts: 666
Likes: 5
It sounds like you have a floating ground wire on one of the pass side turn signal lamps. When the parking lights are off, it is getting its ground through all of the parking lights. When the parking lights are on, both sides of the turn filament are at 12V.
FTE Legend
Joined: Jul 2010
Posts: 32,875
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From: Northeast, OK
I agree completely and was about to say the same thing, though surely not as well.
Posting Guru
Joined: Jan 2012
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From: Dallas, GA
I've heard this term "floating ground"...what exactly does that mean?
FTE Legend
Joined: Jul 2010
Posts: 32,875
Likes: 48
From: Northeast, OK
It means the ground at that point isn't truly connected to chassis ground. So it gets pulled above ground, meaning above zero volts, depending on what happens.
Posting Guru
Joined: Jan 2012
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From: Dallas, GA
Gotcha....thanks Gary
FTE Legend
Joined: Jul 2010
Posts: 32,875
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From: Northeast, OK
Ground problems are, IMHO, the hardest of all wiring problems to diagnose because they can have so many symptoms. In this case, for instance, you get one symptom with the headlights on and another with them off.
And, given the sensitivity of a DVM, checking the ground with everything off wouldn't show the problem as the DVM "sees" ground through the various bulbs that are grounded. Since the DVM pulls so little current the bulb looks like a solid wire to ground. But, with the bulbs on that ground will "float" up to something between battery voltage and ground.
And, given the sensitivity of a DVM, checking the ground with everything off wouldn't show the problem as the DVM "sees" ground through the various bulbs that are grounded. Since the DVM pulls so little current the bulb looks like a solid wire to ground. But, with the bulbs on that ground will "float" up to something between battery voltage and ground.
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Elder User
Joined: Apr 2009
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From: San Diego
I get what you are saying. I have to modify my symptoms a bit though, I was checking some of my wiring and found nothing yet. I paid more attention to exactly what it was doing and the turn signal lamp comes on when the lights come on, but it does actually blink with the blinkers on.
About the speed of the blinkers. With this floating ground I am assuming that this may be the cause of the slower blinkers with the truck not running?
The theory stems from using led lights on say a motorcycle, they blink faster because of the decreased resistance in the circuit (filament bulb has more resistance and draws more current than a led light) increased resistance say adding by adding more bulbs or wiring to the circuit through faulty wiring causing the slower blinking signals.
I guess I am going to have to look a lot closer to the wiring...
About the speed of the blinkers. With this floating ground I am assuming that this may be the cause of the slower blinkers with the truck not running?
The theory stems from using led lights on say a motorcycle, they blink faster because of the decreased resistance in the circuit (filament bulb has more resistance and draws more current than a led light) increased resistance say adding by adding more bulbs or wiring to the circuit through faulty wiring causing the slower blinking signals.
I guess I am going to have to look a lot closer to the wiring...
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Elder User
Joined: Apr 2009
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From: San Diego
And I am thinking that I may need to cleanup the ground connections at the rear signals, and maybe tie them to the chassis as well as the sheet metal of the bed that they are already attached to.
FTE Legend
Joined: Jul 2010
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From: Northeast, OK
I get what you are saying. I have to modify my symptoms a bit though, I was checking some of my wiring and found nothing yet. I paid more attention to exactly what it was doing and the turn signal lamp comes on when the lights come on, but it does actually blink with the blinkers on.
About the speed of the blinkers. With this floating ground I am assuming that this may be the cause of the slower blinkers with the truck not running?
The theory stems from using led lights on say a motorcycle, they blink faster because of the decreased resistance in the circuit (filament bulb has more resistance and draws more current than a led light) increased resistance say adding by adding more bulbs or wiring to the circuit through faulty wiring causing the slower blinking signals.
I guess I am going to have to look a lot closer to the wiring...
About the speed of the blinkers. With this floating ground I am assuming that this may be the cause of the slower blinkers with the truck not running?
The theory stems from using led lights on say a motorcycle, they blink faster because of the decreased resistance in the circuit (filament bulb has more resistance and draws more current than a led light) increased resistance say adding by adding more bulbs or wiring to the circuit through faulty wiring causing the slower blinking signals.
I guess I am going to have to look a lot closer to the wiring...
As for slow blinking, the old style blinker used heat caused by the current flowing through the circuit to cause a bi-metallic strip to bend and break the connection, thereby turning the lights out. When it cooled the connection came back and the lights came on. If the voltage in the system is low, such as at idle, there isn't as much current so not as much heating and the thing doesn't blink as fast. If you put LED's in there is almost no heating because the current is so low, so they may never blink.
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Elder User
Joined: Apr 2009
Posts: 922
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From: San Diego
Yes they do blink, kind of weird. I am thinking it is a defective bulb or wiring at the front bulb. All I did is remove and re-install the front pass side light (while my parking lights were on) and it went away. However that bulb is not a bright as the others.
Guess I'll find out soon enough.
Guess I'll find out soon enough.
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