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Headlight plug diagram

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So if I wanted to power some grill letters I could tap the grey/blue (GRY/BU) on the left side?
I honestly don't know. Depending on how much draw there is from the letters, it might create a fault on the DRL circuit. The FET is going to act like circuit breaker when it hits whatever preset level of load/short range it's programmed to see.

Not having played with this my first try would be the YE/VT wire coming from the battery junction box because it says "with headlamp relay energized". I don't know if it get's energized when the vehicle is started or after the headlight knob is is turned to any of the on positions. Wiring diagram isn't very clear so I'd have to dig into the workshop manual.
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swooshdave

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I honestly don't know. Depending on how much draw there is from the letters, it might create a fault on the DRL circuit. The FET is going to act like circuit breaker when it hits whatever preset level of load/short range it's programmed to see.

Not having played with this my first try would be the YE/VT wire coming from the battery junction box because it says "with headlamp relay energized". I don't know if it get's energized when the vehicle is started or after the headlight knob is is turned to any of the on positions. Wiring diagram isn't very clear so I'd have to dig into the workshop manual.

Blanco used one of the wires on the headlight plug. He also used red wires for both power and ground which makes Baby Jesus cry. A lot.

Link takes you to the wiring part of the video directly to instill the maximum amount of discomfort.
 

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I wonder if there's a way to get inside the headlight housing to tap into the actual LED for a relay signal? There must be wiring or circuitry inside the headlamp that could be accessed, right?
 

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I honestly don't know. Depending on how much draw there is from the letters, it might create a fault on the DRL circuit. The FET is going to act like circuit breaker when it hits whatever preset level of load/short range it's programmed to see.

Not having played with this my first try would be the YE/VT wire coming from the battery junction box because it says "with headlamp relay energized". I don't know if it get's energized when the vehicle is started or after the headlight knob is is turned to any of the on positions. Wiring diagram isn't very clear so I'd have to dig into the workshop manual.
Did you ever find out how much added power you can take from one of these circuits with out being a problem?

I was thinking of using the parking light wire or the license plate light to get power for adding a light in the back as these turn on when a door opens or is unlocked or locked.
 

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Didn't dig into it much since Ford really doesn't provide that information. You would essentially need something like an electronic relay that doesn't use the signal wire for power, just senses voltage or voltage drop and then triggers the load side. Standard and even micro relays require a certain amount of voltage or amperage in order to produce the field that moves the load contacts. You'd probably need to search for an electronic relay that has a 12V milliamp trigger with whatever amp load side your accessory calls for.
 

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jalawson

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Didn't dig into it much since Ford really doesn't provide that information. You would essentially need something like an electronic relay that doesn't use the signal wire for power, just senses voltage or voltage drop and then triggers the load side. Standard and even micro relays require a certain amount of voltage or amperage in order to produce the field that moves the load contacts. You'd probably need to search for an electronic relay that has a 12V milliamp trigger with whatever amp load side your accessory calls for.
Here’s a common issue across all my Ford vehicles that has always puzzled me because there should be an easy fix. Anytime I use aftermarket lights (fog or headlights), regardless of the brand, the light will flicker when the engine starts from the auto start stop feature. This never happens for any of the OEM lights.

The engineer in me thinks there’s a capacitor or something internal to the Ford light assemblies that prevents the light from experiencing the voltage drop during engine start. Any thoughts or ideas what that could be?
 

Nibroc99

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Here’s a common issue across all my Ford vehicles that has always puzzled me because there should be an easy fix. Anytime I use aftermarket lights (fog or headlights), regardless of the brand, the light will flicker when the engine starts from the auto start stop feature. This never happens for any of the OEM lights.

The engineer in me thinks there’s a capacitor or something internal to the Ford light assemblies that prevents the light from experiencing the voltage drop during engine start. Any thoughts or ideas what that could be?
You'll want to put a capacitor in line with your aftermarket lights if this is really that big of an issue. However, I have LasFit SAE Fog and SAE Driving light pods that I use on-road, and they don't flicker when I use auto start stop. I have a wildtrak 4-dr so I'm not sure if it's got a bigger alternator or battery perhaps.
 

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Here’s a common issue across all my Ford vehicles that has always puzzled me because there should be an easy fix. Anytime I use aftermarket lights (fog or headlights), regardless of the brand, the light will flicker when the engine starts from the auto start stop feature. This never happens for any of the OEM lights.

The engineer in me thinks there’s a capacitor or something internal to the Ford light assemblies that prevents the light from experiencing the voltage drop during engine start. Any thoughts or ideas what that could be?
Not really. The old "standard" of 10.5V-11.0V used to be the range modules would freak out and either throw faults or stop working. If you had a battery with a state of charge below, say 65%, and the ASS was kicking in several times on a drive, it's possible you would have a momentary dip in voltage that would cause it to freak. I assume they built in some capacitience? to stabilize a dip for a certain millisecond range but have no idea what that would be.

Absolutely no engineer so if someone knows exactly how this works feel free to educate me. The BCM circuits use transistors on the hi/low, turn, DRLs, park and turn outage, which are essentially small relays. When you turn them on with the switch, the headlight itself is supplied from a headlight relay. The other stuff appears to be controlled directly from the BCM, no idea what the load limits are per circuit.
 

jalawson

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You'll want to put a capacitor in line with your aftermarket lights if this is really that big of an issue. However, I have LasFit SAE Fog and SAE Driving light pods that I use on-road, and they don't flicker when I use auto start stop. I have a wildtrak 4-dr so I'm not sure if it's got a bigger alternator or battery perhaps.
Are those on Aux switches or the fog/headlight harnesses?
 

Nibroc99

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Are those on Aux switches or the fog/headlight harnesses?
Not that I'm aware of. I do have the aux lights I'm running hooked up to AUX 1 though.
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