Re-Wiring Fog Light
05-11-07, 03:12 PM
#1
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Re-Wiring Fog Light
I am wondering if anyone know or have already try to re-wire the fog light, so it will light up without turning on the headlight???
Please let me know if anyone know how to do so, thank you all.
Please let me know if anyone know how to do so, thank you all.
05-11-07, 11:59 PM
#2
It cannot be done using the existing switch, as its signals are multiplexed with all the others in the stalk and sent to the "front controller" under the hood, near the "FR Fog" relay, and the controller separates all these signals to drive various relays for the headlights and the horn.
If you want to add a new switch, I think you could tie into the control side of the Fog relay coil, then ground it through a toggle switch.
The relay lives in the relay/junction block box behind the LF headlight, next to the ECU. Once you find the relay, a voltmeter will show both sides of the coil are at +12V when the lights are off, and one side is 0V when they are on. This is the point where the switch gets connected.
Just don't forget they will remain on even when the car is turned off--the only automatic shutoff is a drained battery.
If you want to add a new switch, I think you could tie into the control side of the Fog relay coil, then ground it through a toggle switch.
The relay lives in the relay/junction block box behind the LF headlight, next to the ECU. Once you find the relay, a voltmeter will show both sides of the coil are at +12V when the lights are off, and one side is 0V when they are on. This is the point where the switch gets connected.
Just don't forget they will remain on even when the car is turned off--the only automatic shutoff is a drained battery.
Last edited by DrexLex; 05-12-07 at 12:11 AM.
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