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Halogen head lights

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donandmax

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Walmart sells halogen headlights for a little over 5 bucks each.I installed them in my midget (79) and they work well. Although I have never driven any distance with these on, I understand halogens should be used with a relay switch (easier on the on-off sw.) But I dont seem to have any problems at all using them with the stock set up. Is it that more expensive halogens draw more current and can cause switch failures ? Thus the need for a relay ?
Thanks
Don M
 
No the wattage draw should be the same. I think its fixed at like 55w and 65w or something for on road headlight bulbs. These bulbs just use a different type of filament and get more light out for the same power. I replaced one of mine with a halogen because it went bad and the other is just a normal sealed beam. I can't really tell a whole lot of difference. i thought of replacing them both with the fixed globe type where you use the replacement filament like the newer cars but they are expensive.
 
On the same thought I had trouble with headlight switches. The one that was in it when I bought the car burned up and then I bought two new ones that burned up after about 4-6 months each after use , so I replaced it with an industrial type switch with higher rated contacts. I think the problem was that I was driving during the winter months and worked a rotating shift where I would leave for work at either 6am or 6pm but either way it was driving in the dark all the time. I also had the original gen and running the lights, heater fan, wipers, etc kept the battery at a low level most of the time and this made the lights pull more amps at the lower voltage which might have added to the problem. Still at 40 bucks a pop, I wasn't going to keep putting in switches.
 
The halogens shouldn't take any more current if they have the same wattage. I had a problem where the low beam contacts in my dimmer switch overheated and lost contact, so I put the relays in to overcome that problem. Not sure if it was just a lousy reproduction dimmer switch, but the relays helped in other ways too. Now when I turn the headlights on the dash lights aren't as dim, the wipers run faster, and the rest of the lights are brighter. I also took the opportunity to put fuses in the headlight circuit, which suprisingly didn't exist. Wires make good fuses, but tend to cause lots of other problems when they blow.
 
When I got Bugsy, driving at night could have been enhanced by holding a 2 D Cell Flashlight out the window. Headlights were so crappy driving could be described as dangerous. I installed headlight relays on Bugsy and it made a tremendous difference in headlight brightness. Try https://www.partsexpress.com. 12VDC DPDT Relay 20 Amp for $2.64 and a Relay Socket for $1.75 x 2. They also can provide a Wiring Diagram for Headlight Relays. Go to their site and Search under keyword Relay.

I mounted on right inside fender right by where wires come out of harness for headlights. I added fuses for safety sake and connected power directly to battery(Again Parts Express or Radio Shack). Cut and solder wiring, use Heatshrink as well. Parts Express sells Bulk Heatshrink all colors in 3' pieces as well. I have NFI in any of the suppliers mentioned.

This was a simple addition and interesting engineering exercise to do. Whole thing cost me < $15 including 20A fuses, fuseholders, and some wiring I had on the garage wall. This is a worthwhile project and really made a difference in driving at night.

Here is a useful link on Headlight Relays and Installing them.

https://www.danielsternlighting.com/tech/relays/relays.html
 
The closer you can get relays and powersource to the headlights the brighter the headlights will be. I on the other hand don't have a Bugeye that looks as nice and unmolested as your's. Relays really can go anywhere. You just need to be able to tap into the harness.
 
I'm so not there yet but could someone please explain the concept of relays - I can't figure out how they would boost the voltage except by lowering resistance which - if you are installing near the light is at the end of the "hose" anyway - enquiring minds need to know

thanks all
 
By removing the headlight load from the main wiring harness and supplying a separate set of power leads for the headlights, you don't get as much voltage drop through the main wiring harness, or through the old headlight and dimmer switches. Putting the relay near the headlights doesn't make much of a difference, other than it's more convenient to put the relays in where the left and right wires join together. There's a grounding lug near there too, which is convenient to connect the negative side of the relay coil.
 
I added a relay to get the headlight load off the old headlight switch. Working as intended.
 
Hello Kim,

"this made the lights pull more amps at the lower voltage"

electricity doesn't work like that. Lower voltage means lower current draw. The stated wattage is at rated voltage.

The point about relays and less voltage drop is actually due to the size of cables used to supply the load, if you use the same size cable the voltage drop will be the same unless the load and supply are very much closer, e.g. a battery very near the front of the car supplying head lights. Better, thought to go for larger cables. Certainly the switch will have less work to do but it was always rated for the full load anyway.

Alec
 
This kind of fits in here, this morning I drove the Midget to work and it seemed like the left side wasn't as bright as it should be. Sure enough I pulled in to park & saw the two lights on the wall, the left side looked brown compared to the right.
Usually when a bulb goes it just goes, what's with this brown light? Anyone see this before?
 
Thanks, I will look at that this afternoon.
 
sparkydave said:
By removing the headlight load from the main wiring harness and supplying a separate set of power leads for the headlights, you don't get as much voltage drop through the main wiring harness, or through the old headlight and dimmer switches. Putting the relay near the headlights doesn't make much of a difference, other than it's more convenient to put the relays in where the left and right wires join together. There's a grounding lug near there too, which is convenient to connect the negative side of the relay coil.
Click to expand...

so in other words, a relay is simply a dedicated run of wires from the battery (fusebox) to the output (headlights) with presumably thicker wire - lower resistance - therefore brighter lights?
 
The relays will also be "new" so their contact resistance will be lower than that of the in-dash switches. (Resulting in slightly higher voltage at the bulbs and less heating of switches).

I have a relay panel on the Mini to operate the high- and low-beams as well as the horn. The horn contact was what drove me to this. My horn wouldn't work at all. No matter how I cleaned the horn button contacts and all the horn ground wire connections the horn would just do an anemic grunt... I couldn't pass enough current. As soon as I installed the relay for the horn it worked perfectly.

I installed Halogens lamps and on the advice of a Canadian acquaintance of mine I installed relays for them as well. My goal was to take the high current off all the dash and dimmer switches. Relays are a lot less expensive.

Another inexpensive source for the automotive relays and sockets is BGMicro.com They sell the Bosch style ISO relays and sockets for prices close to those posted above.

Dan Masters (who is a member of this board) has a firm (https://www.advanceautowire.com/) that has lots of useful LBC wiring supplies and information... some of it specifically on this topic.
 
JPSmit said:
so in other words, a relay is simply a dedicated run of wires from the battery (fusebox) to the output (headlights) with presumably thicker wire - lower resistance - therefore brighter lights?
Click to expand...

Almost; a relay is an electromechanical switch that uses a small amount of current to control a larger amount of current. For example, the starter solenoid is really just a big relay. The headlights are brighter by virtue of having a lower resistance path, and the other lights are brighter by virtue of not having a big voltage drop caused by the headlight current going through the main wiring harness.
 
Hello Dave

"and the other lights are brighter by virtue of not having a big voltage drop caused by the headlight current going through the main wiring harness."

Sorry Dave, but doesn't sound right? The voltage drop in one circuit doesn't affect the voltage in another.

Alec
 
Unless you have a very large one that effects everything in the system. If the source is taxed then all the circuits will be effected.
 
piman said:
Hello Dave

"and the other lights are brighter by virtue of not having a big voltage drop caused by the headlight current going through the main wiring harness."

Sorry Dave, but doesn't sound right? The voltage drop in one circuit doesn't affect the voltage in another.

Alec
Click to expand...

Certainly it does, since they share some of the same wiring. The main wiring harness has some resistance to it, because of a combination of light gauge wire and old bullet connectors that don't conduct as well as they used to. The more current you draw through the main wiring harness, the more the voltage drops for all the accessories running off of it. If you use the relays and a separate, heavier current path for the headlights, then there is significantly less current in the existing wiring harness, so less voltage drop and more voltage available for the rest of the accessories (i.e.: brighter lights).
 
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