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Hi I'm back lol. I have a 70 maverick with a 302/c4 and am having some electrical issues.

I took out the blinkers up front (under the bumper) and decided to just use the park lamps in the grille as turn signals.

First off Idk how well the front signals worked before I did this. And second of all the lights in the grille look like Walmart amber oval shaped lights (installed by previous owner, two wire hookup)

The polarity is correct and they are plugged into the factory wiring by me splicing the pigtail connector from the stock turn signals.

The issue is, with them installed and plugged in, the lights only flash when the headlight switch is on, and when they do flash, its all 4 lights, and headlights, and dash lights very fast.

With the front signals unplugged everything works normally, I installed resistors designed for led lights (no these are not LEDs but I tried anyways) but no change.

Shouldn't any 12v light work as a park lamp/turn signal, especially since this set and the factory set have only a + and - wire?

I'm going to try again to find the stock set tomorrow in that hellhole I call a shed but in the mean time is there anything else I should look for? Bad ground? Idk thanks for any and all help!
 

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Turn signals and brake lights generally need bulbs with two filaments - one for the parking lights and one for the Brake or turn signal function. The socket is different also with two contacts instead of one.
 

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Fred is of course correct, and also the stock turn signals ground at the bulb socket. This means both of the wires carry +12V independently, one for park (running/clearance) lights and the other for turn signal, each circuit through it's own filament and grounding at the socket. My suggestion is to arrange the grille lights to function identically to the factory schematic, as shown here: 1970 Maverick

Recap: Park light power to the dim filament, turn signal power to the bright filament, and a good chassis ground for the socket. You will probably need to add a grounding wire to ensure that.

David

PS: To help make some sense of the schematic in some areas - the side marker lights also tie into this system, receiving Park light power and grounding through the turn signal filament to ground. When turn signals are used, then both wires are +12V, causing the marker light to go off. This creates side marker lights that flash alternating with the turn signals. A sneaky but common way to get a small flashing light with only one filament.
 
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