OEM fog light wiring question

[Fillups]

I am in the middle of a bumper replacement, removed the OEM capable bumper with factory fogs, and splicing in some aftermarket LED fog lights in the new bumper. Rather than worrying about finding a compatible plug I am just going to hardwire the new lights into the harness. Just checking my electrical theory here… The common wire between these two lights is black with a green tracer. I assume that is the ground?

On the driver side. The second wire is solid brown, and on the passenger side the second wire is yellow with a red tracer. But both sides have the black with a green stripe. Here are a couple pics.

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[CalvinT]

The common wire between these two lights is black with a green tracer. I assume that is the ground?

Black is normally a ground wire in automobiles. Ford uses black with various color tracers for ground wiring in all the diagrams I've seen.

But instead of guessing, use a volt/ohm meter and measure them.

I'm surprised that the supposed hot wires are different colors. But then I don't design wiring harnesses.

 

[flip]

 

[Fillups]

Black is normally a ground wire in automobiles. Ford uses black with various color tracers for ground wiring in all the diagrams I've seen.

But instead of guessing, use a volt/ohm meter and measure them.

I'm surprised that the supposed hot wires are different colors. But then I don't design wiring harnesses.

Good idea, but not the most convenient since the harness is unplugged and on my kitchen table where it’s warmer.

I guess I can plug it back into the car long enough to test with the lights switch turned on.

 

[Fillups]

Black / green = Ground, thanks!

 

[CalvinT]

Good idea, but not the most convenient since the harness is unplugged and on my kitchen table where it’s warmer.

I guess I can plug it back into the car long enough to test with the lights switch turned on.

I was thinking just measuring resistance from the black wires to ground. Don't need a harness to do that. You have to strip them anyway for the crimp connector.

 

[4x4TruckLEDs.com]

Why would you start cutting wires when there are tons of readily made pigtails already out there to plug into your factory harness and into your new lights? Or at the very least, you can cut the pigtail and hard wire it into your lights so you're not cutting/splicing a factory wire?

 

[CalvinT]

Why would you start cutting wires when there are tons of readily made pigtails already out there to plug into your factory harness and into your new lights?

Looks like it's a done deal.

 

[flip]

Ford does or at least did some odd stuff with wire colors, especially ground. Black/green, black/white, black/red, black/grey, etc. I've even see some black that were power. The reason for multiple ground combos is mainly for testing identification since you could have 10+ ground circuits going through one harness and if you're trying to find a specific wire to check open/continuity, if they're all the same color there's a high probability of getting the wrong one.

Don't ask how engineering determines what color combos they use, I have no idea but was told they were going to go with a one piece harness (no or few inline connectors) sometime this decade. That was a couple years ago and haven't heard anymore about it but that could really make fixing or replacing, interesting.

 

[NC_Oak]

Looks like it's a done deal.

Ha! right? can't put the toothpaste back in....

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