# Adapting the headlight wiring after a Headlight upgrade on the VW T5



## wildebus (Jun 26, 2016)

My "How To" for adapting the headlight wiring after a Headlight upgrade on the VW T5
DISCLAIMER : This is how *I *installed it and is not a recommendation. Follow at your own risk


Anyone who has driven a T5 Transporter will not have been over-awed by the performance of the Headlights 
The standard "commercial" headlights have a single H4 bulb in a fitting that doesn't make the most of it's limited ability. For the first few months (I bought this Shuttle last November), I just ran them with an upgraded Philips H4 Extreme bulb fitted.
These were better, but still not fantastic, so I opted to replace the actual headlight assemblies themselves.
So started with this ...






And changed to this ...





By default, when changing from the T5 Commercial headlights (using the Dual-Filament H4 Bulbs) to Projector Type headlights like the Caravelle, Angel Eyes or "R8 Style" lights, the Dipped Bulbs will go off when the Main Beam is activated (this is because a dual-filament bulb like an H4 will overheat and fail if both filaments are powered up for a length of time). It is not actually necessary to make any changes to wiring if you don't want to, and the headlights will work fine, but they will not be as effective as they possibly could be. The Caravelles out the factory will have both Main and Dipped active when driving on Main Beam, and the following is a simple way to do this on a non-Caravelle with upgraded Headlights... 

Wiring Components:

*12V 40A Relay and Holder*.  Plenty around on eBay - here is one example ... Relay. Note that depending on what you buy, the pre-wired colours will vary, so I will make no reference to any colours for the relay itself!
*Fuse Holder and Fuse*. it is ESSENTIAL to protect the 12V supply to the relay with a fuse.  I would recommend a fuseholder with a blade fuse as that is the type used in the vehicle generally. Again, loads on eBay. I would fit a 15A fuse personally to protect a pair of 55W bulbs on a 12V circuit
*Ring Terminals* for the Battery +12V and Earth connections
*Wire!*.  Suitable wire gauge.  Consider each bulb is drawing around 5A and could be on continuously for many hours.  Decent wire will also minimise voltage drop, it is not just about current capacity.

To do the wiring, I would consider a minimum of a soldering iron (plus solder!), wire strippers, insulation tape, heat-shrink tubing and a terminal crimping tool be availble.  None of those tools are expensive nowadays, so there is no reason not to have them if working on a vehicle.
Ideally you would also have some thin flexible conduit to run the wire in from the relay to the offside-headlight at least to provide protection.
So for the wiring, see the attached diagram, but in summary:

Main Beam connection wire on Nearside is tapped near the Headlamp plug and a wire is run to *pin 86 *of the Relay Socket
Dipped Beam connections on both Nearside and Offside are tapped near the Headlamp plugs and wires run from *pin 87* of the Relay Socket
*Pin 30* of the Relay Socket is connected to the battery via the fuse holder
*Pin 85* of the Relay Socket is connected to a grounding point (battery or chassis are suitable, whichever is preferred (I used Battery -ve)
Obviously protect all soldered connections with heat-shrink tubing and/or insulation tape as appropriate.
If it is desired to not tap into any of the original VW wiring to do this (some people are concerned about doing this, or just want to leave it untouched) it _is _possible to do the wiring inside the headlamp itself, identifying the right wires to tap into, but I personally see no reason to do that and simply would not do that.

*Wiring Diagram*





The Diagram above also includes some DRL wiring (dotted lines).  I bought a T5 Specific DRL set to install with the new headlights as it made sense to do this at the same time. 
I bought this kit  - Not the cheapest set of DRLs around, but they are sized specifically for the VW T5, the wiring and installation guide is specific to the T5 and contains all you need to install except for a 76mm hole cutter if you have no fog lights already in place to swap out.


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## travelvolts (Dec 1, 2016)

*Minor issue*

There is one small problem with this mod. As you now have both dipped bulbs connected together you have removed the individual fuse protection and if a fault develops on one side it will blow both fuses leaving you with no dipped beams at all. For better protection fit 7.5 amp fuses in each wire to the dipped beams.


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## IanH (Dec 1, 2016)

wildebus said:


> My "How To" for adapting the headlight wiring after a Headlight upgrade on the VW T5
> DISCLAIMER : This is how *I *installed it and is not a recommendation. Follow at your own risk
> 
> 
> ...



Impressed though agree re fuse protection. Real question is, did you draw the diagram and, if so, what software package did you use (visio??)


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## oldish hippy (Dec 1, 2016)

you changed the nose as well


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## Deleted member 52918 (Dec 1, 2016)

Hi, does this mod increase the brightness of the headlights in lumens but not watts?

There's a lot of talk of the newer lights & upgrades being a lot brighter than the old halogen ones.
People are complaining of being blinded by them, so eventually the government will have to step in & put the light output in lumens rather than watts.
Personally I don't think it can come soon enough, getting fed up with 55watt equivalent but twice the light output headlights blinding me!!

Phill


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## wildebus (Dec 1, 2016)

travelvolts said:


> There is one small problem with this mod. As you now have both dipped bulbs connected together you have removed the individual fuse protection and if a fault develops on one side it will blow both fuses leaving you with no dipped beams at all. For better protection fit 7.5 amp fuses in each wire to the dipped beams.



Indeed Martyn, and I have modified my Mk 2 loom setup to add a 10A fuse each side.


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## wildebus (Dec 1, 2016)

IanH said:


> Impressed though agree re fuse protection. Real question is, did you draw the diagram and, if so, what software package did you use (visio??)


Yes, and MS Visio


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## wildebus (Dec 1, 2016)

time4t said:


> Hi, does this mod increase the brightness of the headlights in lumens but not watts?
> 
> There's a lot of talk of the newer lights & upgrades being a lot brighter than the old halogen ones.
> People are complaining of being blinded by them, so eventually the government will have to step in & put the light output in lumens rather than watts.
> ...



It turns on all 4 bulbs. This is typical of all modern, maybe higher end vehicles which employ separate bulbs for main and dipped beam.  So 4 on rather then 2, I guess it increases the TOTAL wattage and also the lumens compared to just two bulbs on.  Doesn't increase the power of an individual bulb, and shouldn't actually make any difference to oncoming traffic if the driver uses their lights correctly as the main beam is not deployed with oncoming traffic of course 

What makes this particularly useful to me personally is as when the main beam is on, the dipped is on - and that means the road remains illuminated directly ahead as well as further into the distance. I drive a lot on totally unlit county roads where all manner of widlife like to roam and dart about, so it helps give me a fighting change of spotting them before they become roadkill.


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## wildebus (Dec 1, 2016)

oldish hippy said:


> you changed the nose as well



I do like a bit of Chrome embellishment :dance:


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## wildebus (Dec 7, 2016)

Thought I would add a photo of the revised "Mk2 loom" for the headlights that I mentioned (not updated the wiring diagram yet)





15A fuse between battery and relay; 10A fuse between relay and each of the dipped headlights
(Fuse group below...)





And conduit to protect the additional cable as it routes from relay/fuse set to offside headlight.

This same loom could also be used to power up additional spotlights in a safe and reliable way :dance:


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## Bizmo (Feb 18, 2019)

wildebus said:


> Thought I would add a photo of the revised "Mk2 loom" for the headlights that I mentioned (not updated the wiring diagram yet)
> 
> 
> 
> ...




These images have stopped working, do you still have them?


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