Dumb down headlight relays for me.

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midwest

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I'm looking into option on my headlights for my 86 K 20. I don't drive it much at night at all so I can't justify the higher end LED's like Holley's. I should start by saying unfortunately I know nothing about electrical and wiring and just can't seem to figure it out. Am I reading right that adding relays to even the stock headlights will help them preform a little better? I will likely just go get 4 new stock headlights and get them adjusted correctly. However if there is a cheap and easy (for someone who can't wire ****) way to get better performance I might as well do that. Now off to youtube to see how much trouble wiring relays is....
 

dvdswan

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If you're not much of a night driver, then why even do the effort of adding relays? There are sealed beams that are a cleaner white for better performance.
 

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i'll jot some things down, hopefully it'll help you decide on a path.

relays allow a 'stock' switch that CAN'T handle much 'power' to use a load (super power headlights) that requires more.

relays, in this case, wouldn't do much of anything for stock headlights or stock spec headlights.
in theory, the relays would allow you to power the stock headlights with less path loss.
(the headlights would get 'juice' from a shorter wire to the battery but i doubt you'd notice)

as the post above, a newer, brighter, clearer, higher color temperature set of headlights that are STOCK ELECTRICAL specs will probably give you what you want without changing the wiring.

so, for occasional night driving, a new set of sealed beams (stock type headlights) is a good bet.

good luck,
'monkey
 

fast 99

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LED lamps use less amperage and provide better/more lighting. Stock wiring will work.
However, it would require aftermarket lamp housings such as Hella or Bosch and bulbs.

If purchasing replacement "stock" bulbs that claim to provide better lighting read the amp or wattage requirement. 4 higher performance bulbs could exceed the capacity of the OEM system. Also check local laws. Aftermarket lighting isn't legal in every state.
 

Grit dog

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^ What @WebMonkey said. Except folks report better performance out of OE type bulbs as well.
First, relay kits are cheap(like $30 on Scamazon), easy to install and virtually plug n play. Only wiring that is required is a fused connection to the battery or a similar power source that is not limited.
Other advantages are, less taxing on old marginal wires and electrical system.
Inherently better/cleaner power than running full “power” from source back to cab (headlight switch) and back to lights.
I haven’t done our truck yet. Have had the kit for a while but waiting until I redo the battery cables and add a fuse panel under the hood for accessories.

It’s worth it, even if not a lot “brighter “ for other reasons mentioned above.
 

midwest

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Thanks all

Grit dog, that goes along with what I had heard. Even with stock lights there can be some benefits to having relays. I just wasn't sure I was understanding it correctly. The other thing I need to look at is my truck itself. It was originally a 77 and after I bought it I got a donor body off of an 86 and a couple friends (along with a couple hundred beers) and we swapped everything over. I know there were a few wiring things that had to be done but again I was just handing out beers while they were doing the work. I have had the truck for around 15 years and no issues so I assume they most things correctly. Its been so long ago now, I can't remember what the issue was but the only hickup we had at the time was the wipers only work on one speed. I have lived with that.
But I assume all of the headlight wiring is the factory wiring from one of the trucks...
 

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I used some of the cheaper kits, purchased from LMC and online, and got mixed results. On one, my stock headlights were brighter but when a bulb burnt out, neither worked. On others, I had one side brighter than the other. Just weird stuff.

I am going to be purchasing the kit from Candela Enterprises. https://ceautoelectricsupply.com/
I've plugged this guy a few times on here already about his incredible battery cables but he takes the time to answer the phone and will walk you through your tech questions as it related to his products.
 

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I wish I had gotten a before photo, but I didn't. All I can say is I almost ran over a guy that was jogging in the road and it was on a local street with streetlights, and the streetlights washed out my headlights. I had the relay kit, it was just a back burner project, but it got put on the front burner after nearly running that dude over. This is the end result, sealed beam halogens, 1965 C20. Yes it improved output, but the sealed beams still couldn't compete with the peel-your-skin-intensity-modern lighting. Relays are worth the effort, and later, if you choose to go with 9003/H4 halogens or feel like blinding everyone on the roadway with you, LEDs, and your wiring will be setup for it.


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DoubleDingo

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I used some of the cheaper kits, purchased from LMC and online, and got mixed results. On one, my stock headlights were brighter but when a bulb burnt out, neither worked. On others, I had one side brighter than the other. Just weird stuff.

I am going to be purchasing the kit from Candela Enterprises. https://ceautoelectricsupply.com/
I've plugged this guy a few times on here already about his incredible battery cables but he takes the time to answer the phone and will walk you through your tech questions as it related to his products.
Thanks for posting up that link, I had forgot about you mentioning him and his kicka$$ products. I'll be ordering my relay kit from him instead of LMC. Come on Friday, Friday is payday!
 

Bennyt

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When I've come across a one side brighter than the other issue, first thing I check are the grounds. Your results may differ, success is not guaranteed.
This was on my '06 Suburban and I did it when the truck was fairly new. It would alternate side to side which was brighter, then I switched to a kit from LMC and had the problems with a bulb burning out and taking out both sides. Tried 2 different kits on that truck and could never get it to function well. Most of these kits have cheap wiring from overseas and suspect relays/ connectors, etc. Definitely not a ground issue on this vehicle.

On my "89 Jimmy(K5) I used LMC's kit and had intermittent luck. I used a few different electrical products from LMC and none functioned as well as stock. Tried to deal with LMC tech support and got nowhere on multiple purchases. Unless I know the brand that they are selling, I've been using them less and less. I ordered a nut for the hood pin and a new hood pin which is fine thread and they sent me a course thread nut. I sent them an email letting them know and they requested pictures. I sent them pictures of the nut and they said it matched what was on the shelf so it must be right and mailed me another coarse nut. I tried explaining that there was a mismatch and they couldn't figure it out so I gave up. I wasn't worried about the 50 cents, I was trying to resolve their issue.
 

timbritton

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I made my own kit 2 relay’s. One for high beams one for low beams. Lights were noticeably brighter. Factory light switch doesn’t allow full voltage for headlights because of restricted current flow caused by substandard wire.
 

Matt69olds

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Inspect and clean the electrical terminals of the headlight sockets, make sure the grounds are clean and tight. Check the ground that goes from the negative battery post to the radiator support, and from the back of the engine to the firewall. That might make a huge improvement.

Get a cheap digital voltmeter.

With the engine idling, low beam headlights on, connect the positive probe of the meter to the positive probe of the battery, put the negative probe on the tan wire of the passenger side headlight. Whatever the meter reads is how much voltage is being lost in the low beam headlight circuit. You can test the high beam by moving the negative meter probe to the light green wire (high beams on of course!) if it’s more than a couple tenths of a volt, then your options are to inspect and clean every terminal of the headlight circuit, or install relays.

Got a pull a apart or enthusiast friendly salvage yard? If so, find a early 2000ish GM car. The best ones are the late 90s early 2000 Buick Park avenues and Lesabre, or the Olds/Pontiac equivalent. At the top of the firewall, just below the windshield is a row of relays. Get several of them, and especially the sockets. Make sure the wires are heavy gauge, and not brittle from age.

Next, watch this

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And this:

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You could buy relays from the parts stores, but they won’t be environmentally sealed. Most late model GM cars have dozens of relays and sockets, making them almost free.
 

Camar068

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i'll jot some things down, hopefully it'll help you decide on a path.

relays allow a 'stock' switch that CAN'T handle much 'power' to use a load (super power headlights) that requires more.

relays, in this case, wouldn't do much of anything for stock headlights or stock spec headlights.
in theory, the relays would allow you to power the stock headlights with less path loss.
(the headlights would get 'juice' from a shorter wire to the battery but i doubt you'd notice)

as the post above, a newer, brighter, clearer, higher color temperature set of headlights that are STOCK ELECTRICAL specs will probably give you what you want without changing the wiring.

so, for occasional night driving, a new set of sealed beams (stock type headlights) is a good bet.

good luck,
'monkey
The old wiring and various connections between the headlights and battery are the issue. They are old, corroded and what not. With a $30 kit from LMC, using the vehicles old power, to the headlights, as a signal for the relays to send DIRECT POWER from the battery eliminates the truck wiring. Your looking at max 4 foot of new wire compared to guessing 12 foot of old wire with various connections/components in the mix as well.

Installing relays on mine, I went from 10.5 volts to them to ~13.5 volts. Obviously they are brighter.

Yes the kit is super easy to install.
 

midwest

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So now I have another question. Like I said before I hardly if ever drive the truck at night. So I went out today to get a look at the headlights to see which ones were working and which ones weren't. When I drove it the other night I could tell a light was out but my bright light indicator on the dash was not working so I couldn't tell if it was a high or low beam that was out. My understanding is that the top lights should be the low beams and then the bottom two come on for the brights. If this is correct are there some bulbs for these trucks that have low and high beam in the same unit? I stood in front of the truck and had my daughter run the lights. When the head lights are on both top lights are lit up. When you turn the brights on the passenger side top light activates a high beam ( in the top light) and the driver side top light goes completely out. The bottom lights are not doing anything in either mode. Now I need to look at the wiring. I am wandering if back in the day when we switched the body over if there was an issue so they didn't wire the bottom two lights and just put dual lights in the top that would run the low and high beams? It is funny I have had this truck for around 15 years and I have never had to change the lights and I have never been in front of the truck when the lights are on....

I took a short video but can't find a way to insert it, I assume it has to be done through youtube or some other 3rd party site...
 

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