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1 Fog Light

Overlandwannabe

Overlandwannabe

2️⃣ Bronze
Anyone ever encounter 1 oem LED fog light (driver side) stop working?
12V power on the black/white wire, nothing on the green.
The harness seems okay all the way back to the connector on the passenger side which works fine.
I did plug in a whole new light assembly and that didn't work either.
Am I missing a bad wire somewhere?
 
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Since I do not have a wiring diagram of your fog lights, there is one thing that is always constant. In any circuit, you need power and ground. Is the green wire supposed to be the ground side of that connector? Check it to ground for continuity.
 
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to keep things simple,....there are two types of wiring used in vehicles.
"Frame" ground and "closed circuit"

d cell battery,.. it has a positive and negative used to complete a circuit (it has no ground)
car battery can be used the same,..... some electrical circuits are not grounded to the frame .....(they do not use negative "as a ground")
some car circuits do use negative as a ground.... (most older cars did before delicate electronics became the norm).

Check to see if both fog light "green" wires are conductive to each other,..... if not the circuit between them is broken

older fog lights mounted to the metal bumper (which was frame ground)
and only one wire ran from a "hot" (12v) switch,.... this made a complete "grounded" circuit.

newer trucks have a full wired positive / negative closed circuit that never uses a "ground"
 
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All that being said, you can bet that the lights on a Toyota do not use the frame as the return patch for power. Even though the battery negative terminal is connected to the engine and frame, the lights do not use it to complete the circuit. I have yet to see a Toyota, Honda or Nissan that used the frame or body of the vehicle to complete the path for lighting. There is always a ground wire.

Put your test leads between your green wire and the black/white wire to see if there is battery voltage when you have the fog light switch turned on. Then, test the other fog light wires in the same manner. How does the operating fog light circuit test?
 
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