1978 C10 front marker lights

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PrairieDrifter

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I did try putting back in the original incandescent bulbs but with the LED relays, they barely would blink. I have 3 types of dual function ordered. Hopefully!!!!!! One will work. They are the wedge 164 bulbs I am replacing.
I thought it was 194 or 168? I may have my numbers mixed up, but I for sure know they are all the same bulb throughout the years. Do you have the old school tube fuses or blade fuses? I know the change was around 79
 

My78truck

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Oh yeah sorry. It is a 168
 

Brett Graves

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Can someone please tell me if the front maker lights on a 1978 Chevy C10 are supposed to blink when the turn signal is engaged? Since I am normally driving, I really do not know if they are supposed to blink or not.

Thanks.
Yeah, they are. They blink with the front turn signals when the running lights are off, and against the blinkers when the lights are on.
 

Brett Graves

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Yes, the ones on front fender - the ones below headlights work fine. I am havimg an issue with the fender side markers. I have switched to LEDs and they are the only ones that are acting up. Headlights off, they blink. Headlights on, they do not blink and do not light up. I checked polarity on bulbs and it made no difference.
They won't work right with LED bulbs, since they don't have a proper ground. I'm replacing mine with LED marker lights instead of just bulb replacements.
 

AuroraGirl

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The side markers can’t blink both headlights on and off with LEDs because the polarity of the socket is changed when it’s one cs the other. My car has turn lamps in front, and they illuminate with park lamps, but switch back with the 3157 mounted forward in the same housing. With an LED, I CAN REVERSE The bulb and change WHICH function it lights for, but not both without more wiring. A simple solution is to wire the bulb to receive power when the front does, but that means not having a legal side markers on a square. My car would still actually have a side marker since the lamp wraps around. You can see about getting a dual “filament”bulb that you can mount in the side marker and then running power for turn to one wire and power to park lamps to the other, then it will increase brightness and blink with,not opposite, your front lamp.
 

My78truck

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They won't work right with LED bulbs, since they don't have a proper ground. I'm replacing mine with LED marker lights instead of just bulb replacements.

I just ordered a set from CARiD. Hoping they solve the problem. :(
 

82sbshortbed

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Did you try flipping them 180* and put back in. That has worked for me a couple of times.
 

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Did you try flipping them 180* and put back in. That has worked for me a couple of times.

Yep, no help. I know they are polarity sensitive. They light up (dimly), blink (dimly) when headlights are off. But when headlights are on, they do not blink at all - the side markers. The parking/signals under the headlamps work fine with headlights on or off.
 

82sbshortbed

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Reason I asked because my led didn't seem very Brite at first flipped it and stuck back in and much brighter.

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82sbshortbed

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Yep, no help. I know they are polarity sensitive. They light up (dimly), blink (dimly) when headlights are off. But when headlights are on, they do not blink at all - the side markers. The parking/signals under the headlamps work fine with headlights on or off.

That sux.
 

AuroraGirl

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Reason I asked because my led didn't seem very Brite at first flipped it and stuck back in and much brighter.

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It almost sounds like your socket allowed power to the right pins but on the wrong orientation and that could be conductive debris or the bulb itself. If it’s working snd doesn’t die, Id think you’re safe. Make sure your housing is sealed, those LEDs domt handle then environment well and my experience is the housings often have a bad seal and then the open contacts corrode
 

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I had electrical gremlins trotting everywhere in the '80 P30 I've been working on, particularly the markers and turn signals Turned out the grounds were all funky. GM saved something(?) by grounding a whole bunch of things at one point. I chased the gremlins when I got tired of trying to figure out where the grounds were and grounded everything individually.
 

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bulbs look like the first picture. I have ordered the 3 different dual function bulbs to try. Concerned that they may be too tall for marker lens. Guess I will see soon. I also ordered the LED side marker replacement lens set up.

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My78truck

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I had electrical gremlins trotting everywhere in the '80 P30 I've been working on, particularly the markers and turn signals Turned out the grounds were all funky. GM saved something(?) by grounding a whole bunch of things at one point. I chased the gremlins when I got tired of trying to figure out where the grounds were and grounded everything individually.

Thing is, when they were all incandescent, they worked fine. So, not sure if it is the ground. But will keep in mind.
 
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