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Dipped beam woes

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Hi all,

my dipped beam headlights are woeful to say the least, all they are good for is to be seen and give zero visibility, how much voltage should i get between dipped beam and high beam at the bulb?
is it just a case of switching the bulbs out? which i hope, but weirdly full beam is fine.

thanks

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No, Crappy lights are 3 things.
Bad Grounds or earths.
Dodgy Connectors that are corroded.
Bad Voltage.

Now you can Check this by measuring the voltage at the bulb.  

Typically you will find 11.5 Volts or less on the elements when they are powered, that is High, or Low.

You can attach a new ground point to the wires and if that increases your lights will be higher in voltage.

1. I personally will tell you that if you haven't replaced your main battery to frame and frame to engine ground cable with new, not clean or replace connectors but replace the cable with 2 off the shelf ones from the parts store of your choice you are doing a disservice to your electrical system. Then you need to clean and replace all other dodgy ground connectors.

2. You can give your Headlights a new brighter look by the addition of 2 or 3 relays.  These relays will shorten the run of wire to the bulbs, you will be applying 13.5V to both elements and that will BOOST the Candela or wattage of the bulb to the design specs.

You will be taking the load off of your headlight switch as the switch will be used to power the relay with minimal current.  

You will be shortening the length of wire going from the battery-to-switch-to-bulb as in 8feet per side longer for the right than the left bulb to about less than 4 feet for both.

If you make your own harness/relay you can use Ceramic Sockets similar to the aftermarket ones for fog lights or OFF-Road lamps.  They take higher wattage and current bulbs, so you can them change to a higher wattage bulb.

To Simulate this effect for study.
Turn on your low beams and shine them on a white surface.  Take a Picture of them….

Now take a Jumper wire of good gauge, and take that from the Battery Directly to your bulb no switch is needed,,,,, See How Frigging brighter they are?

Relaying your Headlights is one of the Best and cheapest safety things  you can do to your car.  

How I did it on my Cabbie, (if you have non-quad lights just leave the pig tails for the quad hi-off.)

I have 2 designs, the first is a two relay system. One relay for high, and one for low.

The second is a 3 relay design that allows the High Beam, and the Low beam to Shine together similar to that moment when you are going from Low to High where both elements are on.


Relaying your Head Lights | Volkswagen Owners Club Forum




What do Divorces, Great Coffee, and Car Electrics all have in common?

They all start with GOOD Grounds.

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4. either poor quality cheap headlamps, or the chrome has peeled off the reflector ;)

Hello my name is John and I'm a dub addict.



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Cheers for the replies, i got them working by replacing the main ground cable to the battery. However now a problem has arisen and i am baffled to say the least.
I run quad lights, dipped beams work grand now, the high beams however are a mystery.
It's all Hella stuff and vag parts so no cheap stuff.
The right (as i am driving) quad light (unsure of its name) does not come on.
The mystery is however, testing over the ground Terminal and positive it is 11v, so there is power, yet it won't turn on.
Plugging in the positive and touching the bulb to the chassis does however turn the bulb on, and reads the same on the multimeter as if i was to place multimeter on the bulb ground Terminal. I have busted so many fuses trying to fix this it's driven me mad ha :p
Any help greatly appreciated
Oh and it's not the bulb as I've swapped them over from the left.
Cheers

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blowing fuses is indicative of a direct short to ground (earth) or over current from corroded sockets or switches.  

As a test, take a standard relay (4 leg).

Remove the Power lead off the inner lamps.
Attach that to the "Pick" leg of the relay
apply earth to the other side of the "pick".

Turn on your high beams, and if they don't blow a fuse then you are now looking at a corroded socket.

If you haven't relayed your Headlights (quads too) do so, this takes the current off the Fuse Panel for the 4 lights and for the dipper switch.  The Power is routed through 2 relays and a couple of fuses to your lights direct from the battery…. Reducing the current through the Fuse Panel and switches (headlight as well as dipper) causes them to last longer and reduces the chances of them releasing the designated smoke signals to indicate an issue.  

If you are still blowing fuses then I would suggest that you replace the main headlight switch…..

also telling us which model you are working on helps me get to the correct schematic.


What do Divorces, Great Coffee, and Car Electrics all have in common?

They all start with GOOD Grounds.

Where are my DIY Links?

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if the bulb works when earthed to the chassis but not plugged in, then this suggests the earth is bad.  the H4 plugs and many others are unsealed on these cars, so the copper suffers.

I had a very nice issue on a friends loom, visually everything looked perfect but no earth to one of his indicators. when I looked closer I found the copper had turned to dust for several inches under the insulation

Hello my name is John and I'm a dub addict.



My wiring diagrams and other documents have moved here:

VAG Documents & Downloads

You'll need to sign into google/gmail for the link to work! (its free!)
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