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Looking for a wiring diagram for my front turn indicators. I currently have small fog lights in front on my "A". I would like to use them for turn indicators. Simple solution if that's all I wanted to use them for but here's the rub. I would like to be able to use them as fog lights and indicators at the same time. I would like to be able to interrupt either light when the indicator is on. Basically if I want to turn left I would indicate so and the left light would interrupt the fog light mode and blink. Your see this a lot on new cars where the turn indicator will interrupt the daytime running lights and begin to blink. Any help would be appreciated.
 

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What you want to do is exactly how most cars use the brake light filament as the turn signal filament also. The problem is that they accomplish this with a set of contacts in the turn signal switch. When the switch is centered, the signal from the brake light switch just runs through the turn signal contacts and out to the rear lights. When the switch is moved to indicate a turn, the contacts on that side are switched from the brake light input to the turn signal flasher input. Unfortunately, that isn't something you can easily adapt to the front lights also.

Basically you need to be able to switch the source for each fog light from the fog light circuit to the front turn signal circuit. One way you could do this is to use a turn signal switch for a car that has cornering lights. These switches have an additional set of contacts that turn on the cornering light on the side you've selected to indicate a turn. Use that cornering light signal to activate a relay on each fog light that switches from the fog light circuit to the turn signal circuit. The normally closed relay contact is connected to the fog light circuit, the normally open is connected to the turn signal circuit. The common terminal goes to the fog light itself. The relay coil is controlled by the cornering light signal from the turn signal switch.
 

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You need a 87A relay.

This is a great video on 87A(5pin) relays that will help explain how they work.

You need to incorporate your flasher into his 87A circuit. But otherwise this wiring layout will work for you.

 

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You could also use the BCM from a late-model GM. It's a flasher, but more. For instance, on my Express van, the DRLs are the front turn signals, so the BCM takes voltage in, gets a signal from the stick on the column, and works magic inside. It's just a matter of finding the pinout and hooking it up.

The 87A relay would also work.
 
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