Bulb question

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jseabolt
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Bulb question

Post by jseabolt » Sat Mar 16, 2019 10:48 am

Years ago I had this episode where the passenger side front turn signal would stop working with the park lights on. And the park light particularly on that side was very dim. It turned out to be a bad ground. I changed all the grounds and other poor connections about 20+ years ago.

Every now and then I check all my lights to make sure they are working. I have usually concentrated on the rear but noticed something funky going on with the fronts. Maybe I never paid any attention to it until now.

I noticed that the front turn signal lights do work but with the park lights on, I can barely see the turn signal light flash. I can see the front driver's side flash but not much better.

It was my understand these dual filament 1157 bulbs which are also used in some brake/park light applications on the rear of cars/trucks with solid red lenses, the brighter 27 watt filament operates the turn/brake and the park is the 8.3 watt filament. That would make sense. You would want the brake/turn to burn brighter when the park lights are on.

I pulled the lense off and turned the park and hazard lights on to observe which filament is burning. It seems the opposite. The park seems to burn brighter than the turn.

The longer filament is what burns with the park lights on and the shorter filament is what burns when the turn signals flashes. I would figure it to be the opposite. That the longer filament is the brighter one.

First thing I thought I'd do is replace the bulb. Maybe the filaments are just weak. No difference.

The connector that goes to the front lights is one of those male/female type so it seems odd to get them reversed.

I thought about just rigging up some jumper wires to reverse the filaments to see if this changes anything.

One other thing. Years ago the turn signals would flash longer. Like every 3 seconds. I installed a new flasher and it fixed the problem. I wonder if it's getting weak.

I'll shoot a video. Maybe it's just my immagination.
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bnam2
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Re: Bulb question

Post by bnam2 » Sat Mar 16, 2019 12:11 pm

I've experienced a similar situation on my Karmann Ghia. I had the park and turn signal wires interchanged at the lamp.
Byas
1965 Fiat 1500 Cabriolet with 1600twin-cam
!971 VW 1302LS Convertible in original condition
1965 KG - under restoration
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jseabolt
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Re: Bulb question

Post by jseabolt » Sun Mar 17, 2019 9:32 am

I shot a video. For some reason they don't seem as bad as today. I have no idea why. The video also doesn't look as bad when videoed with my phone. Maybe it's my imagination or just from working night shifts...

https://youtu.be/JbwofSZMwQw
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bnam2
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Re: Bulb question

Post by bnam2 » Sun Mar 17, 2019 12:01 pm

Looks interchanged to me. The turn should be much brighter than the parking lights. Just reverse the connection at the lamp.
Byas
1965 Fiat 1500 Cabriolet with 1600twin-cam
!971 VW 1302LS Convertible in original condition
1965 KG - under restoration
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jseabolt
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Re: Bulb question

Post by jseabolt » Sun Mar 17, 2019 6:21 pm

bnam2 wrote:
Sun Mar 17, 2019 12:01 pm
Looks interchanged to me. The turn should be much brighter than the parking lights. Just reverse the connection at the lamp.
Well I rigged up some jumper wires at the plug so I could swap filaments to see if there was any change in brightness.

Nope after doing that, the turn signal is in fact weaker.
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jseabolt
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Re: Bulb question

Post by jseabolt » Mon Mar 18, 2019 12:39 pm

Well I think I know what the problem was or might have been. You know those dual barrel connectors? The ones that are female/male so you don't get the wires crossed? It's also used on the polarity for the radiator fan switch. After I unplugged these to test with a jumper wires, I offset each connector so I could rotate the male connector inside the female connector to see if this created a better connection and it seemed to made a difference.
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Re: Bulb question

Post by bnam2 » Tue Mar 19, 2019 2:01 am

Good!
Byas
1965 Fiat 1500 Cabriolet with 1600twin-cam
!971 VW 1302LS Convertible in original condition
1965 KG - under restoration
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