Author Topic: what type of relay do i need?  (Read 149 times)

Offline Rimmy

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what type of relay do i need?
« on: Dec 06, 2017, 15:19:38 »
So this is actually a question for my impreza, but I want to wire in a new set of fog lights. I want them to operate in three modes.
1) Not on at all
2) In concert with the existing fog lights
3) independent

Is a double pole single throw what I'm looking for? I have a three position switch I want to use. Pos 1 will leave the circuit open. Pos 2 will splice in from the existing fog light power line and into pole 1 and Pos 3 will be independently powered and sent to pole 2.

This way I can choose to put the aux fog lights are on even when the stock fog lights (or even headlights) are off.


Or is it just easier to do two single pole single throw relays?
« Last Edit: Dec 06, 2017, 15:40:40 by Rimmy »

Offline Sonreir

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Re: what type of relay do i need?
« Reply #1 on: Dec 07, 2017, 18:46:38 »
I would just use a three-way switch with the middle pole going to the fog lights (or relay providing power to the for lights).

With the poles, A, B, and C, the hookup would be as follows:

A - Power source that is on when the car is on
B - Output to fog lights (or relay)
C - Input from current fog light switch

In the first position, the switch will link A and B, in the second position, no connections (off), in the third position, link B and C.

Make sense?
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