VW T4 Headlights – upgrade basics

Poor VW T4 headlights performance on the VW T4 and how to upgrade them has been a problem pretty much since the vehicle was launched. It is as if Volkswagen didn’t expect T4’s to be used at night! Here we will look at VW T4 headlight upgrade options.

Many owners of this model of Transporter therefore decide to upgrade their VW T4 headlights using a very simple and cheap modification that I shall discuss below.

The headlight upgrade is one of the two essential plug and play VW T4 upgrades that in my opinion are required for modern day living… (The other being the VW T4 Audio upgrade Guide here).

If you have the VW T4 1.9TD or 2.4 with the solid discs (as opposed to vented), you may also want to consider looking at the brake upgrade guide (Guide Here)

VW T4 Headlights

VW T4 Headlights

There are three ways to improve your headlights

  1. Replace them with VW T4 LED Headlights (View price)
VW T4 LED headlight

2. Replace the bulbs only with Osram H4 Night Breakers (View price)

vw t4 headlight bulb upgrade
The brightest VW t4 headlight bulb upgrade

3. Replace the Headlight loom (View eBay price).and bulbs with Osram H4 Night Breakers (View price)

The guide below will discuss the process to do the full upgrade with loom and bulbs.

VW T4 Headlight upgrade – Technical information

The VW T4 headlights original loom suffers badly from voltage drop between the battery and the actual T4 headlights.

This is because the wiring does not go direct (it actually goes a very indirect route!) Coupled with the fact most wiring in T4’s is 20 years or older, so old rusty wires/connectors make the voltage drop even more significant than when the vehicle was new.

This means that the whole 12v never actually makes it to the T4 headlights. Many owners believe that simply fitting better bulbs will work however the biggest gain is to first fix the main issue which is to get greater power to the VW T4 headlight with improved wiring.

How hard is it to fit a VW T4 Headlight upgrade kit?

It really isn’t hard at all and takes no more than 30 minutes to an hour TOPS. Any of the T4 headlight upgrade looms available cheaply on eBay will do the job, one that I would recommend can be found on eBay that works well and is simple to fit.

There are other manufacturers of the part all around the £20-£30 mark.

You can’t go wrong with the plug and play process to install these kits as the plugs should be a like for like swap out of the original VW T4 headlight loom.

The replacement loom adds relays to the circuit and ultimately gives the T4 headlights a direct 12v feed from the battery.

VW T4 headlight upgrade looms are designed to be plug and play using the standard plug fittings on your original loom. Most T4 owners doing this upgrade will also change the light bulbs at the same time to get maximum benefit.

Changing the T4 headlight bulbs is a straight forward job and as you will be working in that area of the vehicle to replace the headlight loom, may as well do these at the same time.

For a huge gain it is well worth the few £ that it costs for the parts.

Relay for Headlight upgrade relay
VW T4 Headlight upgrade relay
VW T4 Headlight connectors
VW T4 Headlight upgrade relay

Best VW T4 headlight bulbs

The brightest VW T4 head light bulbs that are widely accepted as the best bulbs for a VW T4 that and most VW T4 owners go for are the Osram H4 Night Breakers.

Example eBay. It is the H4 fitment that you want by the way for all years of VW T4 headlight so make sure you get the right one.

brightest vw t4 bulbs
VW T4 Headlight upgrade bulbs

VW T4 Headlight loom upgrade installation

There is loads of very good videos on this process on You tube. If you go to this link here there is a good quality step by step walk through for the VW T4 Headlight loom upgrade installation.

However, to put the process into a few words.

  • Pop your bonnet
  • This process is easier with the headlights and front grill removed however it is possible to do it with the grill still in place (if you have small hands like me at least)
  • Disconnect your battery!
  • Locate the current relays and wires that come from your battery. The Relays are located close to your battery on the right hand side of the engine bay and is usually held on with 2 bolts.
  • Undo the bolts on the relays.
  • Follow the wires from the relays and disconnect the cables at all points so that you can remove the Relays and all wires connected to them. You will need to disconnect each headlight along with the point where the relay goes into the battery terminal.
  • You can now remove the relay and all associated cable.
  • The opposite process is then followed.
  • First connect the headlights,
  • Route the cable so that you can easily mount the new relays (to the place that you removed the old one with the two bolts)
  • Refit your headlights and make sure you change the bulbs at this point if that is your intention
  • Make sure all of the cable routing is tidy and away from hot areas of the engine – copy the old routing to ensure it is done correctly.
  • Connect up to your battery.

Safety tip

As you are playing with vehicle electrics here and a fair amount of current travels down these wires, make sure all the connectors are firmly plugged in and the mounting bolts on the relay are done up tightly. We don’t want an electrical fire.

The final stage is to enjoy your new lights and finally you can see more than 20 meters in front of you. A very important job well done.

HID VW T4 Headlight upgrade kits

The above method discussed involves upgrading your loom and headlights is one way I would recommend you to go and only costs about £40 all in.

Most VW T4 enthusiasts go that route, especially if they are confident enough unplugging the cables and installing the new loom.

The method discussed above is the more thorough way to go about brightening your headlights.

That said, if you have researched this topic a bit you will have discovered HID conversion kits, they are all over eBay (Example eBay). They cost around the £30-£35 mark and are a little simpler to fit than a whole loom replacement.

VW T4 Headlight HID upgrade kit
VW T4 Headlight HID upgrade kit

In the picture you can see that you are only replacing the small amount of cable that goes to the headlights.

Whilst this is the easier and marginally cheaper route I wouldn’t recommend it. The main reason is that it doesn’t solve the first issue that I discussed further up about 20 year old cables and voltage loss between the battery and the headlight.

The actual main reason for your dim VW T4 headlights isn’t really being addressed with the installation of this conversion kit you probably won’t see the best benefit from doing it.

I am keen to hear thoughts on the two different methods so if you have first-hand experience installing both options, I’d love to hear from you.

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