Technical Halogen Bulb

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Technical Halogen Bulb

This is the bulb I am replacing, standard I am sure.
 

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You'd only have to uprated the wiring if there was a higher current draw. Do you know if the Halogens are higher?

If yes, the common approach is to use a relay. Have the existing feed switch the relay and wire relay directly to the battery.

cheers, Steve
 
Actually, went back to his site and under the normal bulb it says you can exchange it for the Halogen without other changes or relays. I'll order and take pictures of the difference in light.
 
I have them fitted at the moment and they do make a lot of difference, as you can see in the picture below. I bought mine from Van der Laan and when I spoke to Leo he said they were a straight swop with no problems.

The wiring is not the issue as it should be able to handle the additional current, non-halogen draw 3.75 amps and Halogen 5 amps. The wiring should easily be able to handle that. The issue is the switches and whether they can take the additional current, that is the light switches and the ignition. I have read about someone saying their ignition key was getting hot because of the additional current.

My personal view is it makes sense to fit relays or a relay just to be safe, as I could feel the ignition switch getting hotter when the main beams were on. It makes more sense than burning out one of the switches and being faced with a bigger bill.

Having said all that I don't really drive the 500 in the dark very often, so I don't know why I was bothered in the first place. It just seemed like a good idea at the time.

 
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Yes, I am doing it because my bulb burned out. I would like to take your advice and put a relay in. Any idea how?
 
There is a very good thread on the link below on how to do it with four relays. Personally I think it is a bit unnecessary to fit four relays but I fully understand the thinking behind it. I would go for two one for main and one for dipped.

I will have a look at the wiring diagram and see if I can work out a way of doing it with only two as I need to think about doing it myself. It should be pretty straightforward.
 
From an electrical point of view its straight forward.
12v d.c. micro relays are used.
A new larger wire is run from either fuse box or battery (if battery buy in line fuse holders) to one side of relay contact - other side of relay contact to new larger wire to headlamp.
The original wire to the headlamp bulb is used to "pull in" the relay known as the "coil".

They are very small and can be secreted away in wheel well or mounted next to fusebox.

Cheap and simple - cost less than £15

Always fuse electrics - I lost my Fiat 124 Spider Abarth to an engine fire......very expensive lesson
 
Such bulbs are readily available from Halfords and other car accessory outlets. The standard bulb is a 410, the replacement halogen one is a 2983. (Cars with standard halogen H4 bulbs use 472)
Whilst the halogen "conversion" bulb will give more light, there will be some stray light, as the filament is not in exactly the same place as in the 410 bulb. The light on the garage door is not a clean pattern, so you may get a lot of people flashing at you. Because of this, I don't think they are ever "E" marked, making them illegal to use. (Subject to getting caught, and the bulb being easily removed to check by the policeman) Consider carefully.

Proper way to do it would be proper halogen headlamps, but probably not available for the tiny lamps on the 500, unless they can be replaced by standard 5¾" lamps.

Relays are a very good idea.
 
I did this on my Austin.
As said before, fit two relays securely near the battery or wheel-well where they wont be knocked.
Divert one of the feed wires coming from the steering column lever switch for the main beam to the primary terminal of one relay and from the high beam to the primary of the other. Each relay will need an earthed terminal to complete the circuits.
Take a separate reasonably heavy cable from the battery positive, through inline fuses to each of the secondary terminals of the relays.
Connect the cables which feed the main beam of both of the headlights together at the secondary terminal of relay 1 and do the same with the high beam cables at relay 2.
What will now happen when you activate the driving lights is that the current which previously went out in two supplies to the separate headlights will cause relay 1 to switch and draw current straight from the battery to each headlight. A similar thing happens as you select high beam with relay 2.
I guess why some people use four relays is because you have two redundant cables, from the column switch which still carry current when activated and therefore need safely terminating or removing.
 
Here's a link with visuals of what Andrew and fiat500 are talking about. It's centered on installing horns versus headlights but the concept of what a relay does and how to wire them is very well written.

http://www.rattlebars.com/avalanche/relay_basics.html

With that knowledge, it'll be easier to make sense out of this more cryptic diagram below.

Also as they both say, install fuses on the new wire(s) you'll install between the battery and the relay. I've included a photo of how the wires running to my relays are attached to the battery terminal.
 

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I was googling around and found these with built in fuses that look just the job. It makes sense to drop the fuse rating down. Bob's diagram shows it really well.

[ame="http://www.amazon.co.uk/High-Quality-12v-Fused-Relay/dp/B00EIA8O42"]2x High Quality 12v 30 AMP On Off 4 Pin Fused Relay: Amazon.co.uk: Car & Motorbike@@AMEPARAM@@http://ecx.images-amazon.com/images/I/41Yil-3-DbL.@@AMEPARAM@@41Yil-3-DbL[/ame]
 
I guess why some people use four relays is because you have two redundant cables, from the column switch which still carry current when activated and therefore need safely terminating or removing.

I assume another benefit is that if a relay fails , you only lose one headlight not two.

If you go for the four relay option and want a neat wiring solution, you could go for something like this...
http://www.vehicle-wiring-products.eu/product.php/738/micro-relay-mini-blade-fuse-module

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cheers, Steve
 
I have been meaning to measure the current drawn using a clamp meter just to see the difference and I finally got around to it today.

With a non halogen bulb it draws 3.8 amps and a halogen bulb draws 4.8 amps on main beam, so Ohms law pretty much agrees with these findings.

So as I suspected the wiring is going to be fine but the fact that the lighting circuit takes it earth from the ignition switch an additional 2 amps (1 amp for each main beam) is likely to cook the switch contacts with a lot of usage.

Tony
 
Oh and here is a picture I took today during testing. They are a considerable upgrade on standard bulbs.

 
I took it across the street to a German Auto Electric guy. He put in the relay for my headlights, fog lights, and rewired some other things. He found some not-to-code items as well and fixed them. Interestingly, German law requires the fog light to go out when you put on the high beams so he set that up as well. Not that I plan to drive in fog or have my high beams on :)
 
Has anyone actually done sufficient night-time driving with halogen bulbs to be able to offer an opinion as to whether they really help you see in the dark.
Tony's image clearly shows that they put out some good light, but does that translate into the equivalent of a modern car's lighting; ie. being able to see well enough on an unlit road to be able to maintain more or less the same speed as you can in daylight?

It's getting silly with my lights since I corrected the dynamo output downwards. When a car is close behind me at night I get the solar eclipse effect, where the Fiat is actually casting a shadow from the following car's headlights, which seems to make my own lights seem even less effective.

I'm considering taking drastic measures and no-one except Andrew will like those measures.:D
 
Be brave Tiger!
I have had xenon lights for the past few years but currently find my self with a poverty spec company car whilst i choose my own.
Its a Volkwagen Passat with standard lights and the difference is night and day on unlit roads - i feel like i am peering into the dark.
In my opinion the brightest lights available should be used.
I have fitted LED to my little rascal.
 
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Halogen bulbs will be brighter than the original tungsten bulbs. Modern HIDs or LEDs are better still.
However, halogen bulbs have their filaments in different places in relation to the bulb mounting flange. The original reflector was shaped to put the light from the tungsten bulb in the right place and beam pattern. Whilst conversion bulbs try hard to get them as close as possible to the originals, it is not possible to get them absolutely right. Results can be variable. Bulbs have numbers, used worldwide. The standard H4, twin filament halogen bulb is a 472. The most popular tungsten before these was a 410, with a fat round bulb and a large round mounting flange. There used to be conversion bulbs, usually numbered 2983. These usually gave lots more light, but mostly spread around in the wrong places, and were often no better when driving at night. The DAF cars I used a long time ago used Cibie headlamps and were actually better with a 410 than a 2983. As the bulbs dim with age, replacing these annually proved better than just blinding everyone else with bright light.
Many people were pleased with the conversion bulbs, but not usually the people coming towards you.
If you can find replacement lights, designed for halogen bulbs, that would be the ideal way to go.
 
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