Corner/Marker Light Behavior

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LateOnTheBrakes

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On an 86 are the front corner/marker lights supposed to be on when the headlights are on and blink (brighter?) when the turn signal is on? Mine only light up with the turn signal. The rear corners/markers light up with the headlights, but not turn signals.

I'm trying to make sense of it compared to my newer vehicles that have the corner/marker lights on with the headlights but do not blink.

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FireTruck1984

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Your front corner markers should be on with the headlights and blink with turn signals
 

LateOnTheBrakes

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They are two-wire, single filament, 168/194 bulbs though, correct? How would that work? Increase in current?
 

Matt69olds

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If I remember right, the cornering lamps are powered by the parking lamp wire (brown) and are grounded thru the turn signal lamp. Once you turn on a turn signal, you then have power on both wires of the cornering lamp, causing it to go out.

This is a Saturn, but the principal is the same.

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Itali83

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It’s hard to tell but it looks like your front marker lights aren’t on. The ones under your headlights. If they aren’t, that’s why your side marker lights are on either. You’ve more than likely got a wiring issue from bulkhead connector out to the front marker lights. With no blinkers in and just park lights on, make sure both front marker lights and both front side marker lights are on and go from there.

long story short is the ground for the side marker lights goes through the blinker circuit so when the blinkers come on, the ground turns into a power and the side light goes off. So the front blinker and side marker light will blink opposite from each other when the park lights are on and together when no park lights are on.

Ben
 

LateOnTheBrakes

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I just installed a new painless harness and utilized the stock connectors.

Maybe I am mixing up the nomenclature. Are you saying the turn signal under the headlight should be on and then blink when the turn signals on? Or are you talking about the small marker on the front fender by the wheel?
 

LateOnTheBrakes

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This is correct?

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Lugnut

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This is correct?

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With the headlights off this is correct. The blinker and corner marker will blink on and off together.
With the headlights on the parking light and corner marker light will be steady on,
With the headlights on and the blinker on, the blinker and corner marker will blink opposite of each other.

I wish it was as easy to upload a video from my phone as it is to do a pic.
 

Bextreme04

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I think it depends on the year range as well. Both my 74 and 80 had the front marker light on when the headlights were on. The 74 had the side marker and front marker alternate flashes when the turn signal was on. I haven't checked my 80, but I think it doesn't alternate... I think the two lights blink together.
 

Bextreme04

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With the headlights off this is correct. The blinker and corner marker will blink on and off together.
With the headlights on the parking light and corner marker light will be steady on,
With the headlights on and the blinker on, the blinker and corner marker will blink opposite of each other.

I wish it was as easy to upload a video from my phone as it is to do a pic.

This matches what I have seen on my trucks
 

PrairieDrifter

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Side lamps and front marker lamps act together. The side lamps are on when your switch is on park lights or full lights.

With all lights off I believe both front and side markers flash together. With all lights on they flash opposite of each other. I think the front marker brightens the filament unlike the side marker which for sure flashes on and off instead of just brightening the filament. Just like has been said above a couple times, it is slightly hard to explain lol
 

LateOnTheBrakes

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I understand they should flash together. What I don't know for sure is whether one or both are supposed to be on with the headlights. And if they are on with the headlights should they get brighter (dual filament) and then dimmer with the turn signal, or if they should have one level of brightness and they turn on and off with the turn signal. Basically, should they look like the video I shared of my truck, or the LED example I showed.
 

edward Kish

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Give me an hour to get through a meeting and I'll run out and grab a video of my 78 for comparison.
 

AuroraGirl

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Parking lamps, so headlight switch pulled, should look like my profile pic + the side marker will be lit and so will tail lights. If you use turn signals, it will instead flash the side you signal. When it flashes with lights on, the side marker is flashing when the turn signal lamp in front under headlight is steady. The brightness doesnt change, its a 1156 bulb with a single base, it only has one filament. It could be made to, i suppose, but its not necessary. The flashing indicates direction not brightness.

The tail light vs stop is the exception, the stop light will be brighter than the tail light by design to catch your attention and such. THe rear sidemarker iirc just is one with headlights, no nothing special.
 

AuroraGirl

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I revise my comment. they are dual filament and they do shine brighter, in the front only not sidemarker, than "parking". I will post videos of 1980 gmc round eye videos
this isnt the best representation, but hopefully you notice what i meant. my camera let in too much light and washed out the lights. disregard the color of the front turn and just notice how it flashes. the speed is weird from how it uploaded too
 

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