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VW Transporter T5 – Heated windscreen retrofit

When winter times come in my van its always a horrible time of year as the 2.5tdi T5 is a slow warming engine and the windscreen is so big it hard to scrape the ice, after getting a crack in my current windscreen I started looking at if it possible to retrofit the heated screen out the new T6 into my T5.


After phoning the windscreen company and asking if this was possible and they said the scenes are the same shape/size this was the major part out the way I now started looking at what else was needed.


There are some changes that would be needed and that was there no longer an aerial in the windscreen (no problem as I had fitted a shark fin aerial for FM,DAB and GPS at the rear.

Also the mirror is completely different as all heated windscreens come with rain and light sensor in the screen.

The windscreen would also need wiring but decided this could be done afterwards.

With it all looking good the windscreen was supplied and fitted by Corby Windscreens.

Next was to source a mirror and and after a little hunting found a 2nd hand Skoda Kodiaq one for £14 (Part number – 3G0 857 511AF) with this ordered and new trims from VW this was fitted and clipped into place (this makes the inside look much more modern.


This is the longest and hardest part of the job, (Wiring diagram to follow later)

For me it has to look as factory as possible so I matched as many connectors and pins as possible, I also mounting the relays in to the relay carrier under the battery. My van didn’t have heated rear windows so I decided to use the original heated rear wind switch and connect this the Central Electric J519 as per VW heated rear windscreen is wired (reason for this was it gave diagnostics to the heated windscreen, it also let’s you change the length of activation with VCDS) after plugging in my van to VCDS and checking it listed heated rear window as a option but also in the list was heated front windscreen! Even better.

After find a pin out data for the J519 and finding mine has the pins where heated windscreen should fit, a quick wire up and testing found it picks up the switch press but that is all and doesn’t turn anything on! On the pin data it lists heated windscreen as “not delivered yet” back to connecting the heated rear window route again.

First thing was to make the relay looms and holders, I used the VW relay holders that clip into the factory relay carrier under the battery – The windscreen is 2 separate system, the driver and passenger side runs it own circuit this is why 2 relays are needed and also to handle the current

Next part was to take a fused feed from the battery distribution point next to the relay carrier

Once out the power wires were run up towards the windscreen and signal wire was run into the van and towards the J519 – Central Electric unit

No onto the switch and inside of the van, as mine is a van I didnt have a heated rear window so used a rear window switch, this is wired into the J519 – Central electrics and J519 then provides the feed to the relays, this setup was used as with the diagnostic tool I can adjust the time the J519 keeps the screen on for before automatically switching off.

Once this is completed and all wired in next step is some coding and changed in the J519- Central electric ECU. I needed to add +1 to my original coding to turn on the heated rear window function (for my front window) Once done exit out and lock the vehicle for at least 5 minutes. Now unlock and connect scan tool again and check coding has changed. If yes you can now go into adaptions and change the length of time the window stays on for.

Check everything works and then put everything back together, wait for the frosty morning and enjoy your hard work.

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