Xenon retrofit MK4 caddy

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Banri
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Re: Xenon retrofit MK4 caddy

Post by Banri »

Hey @VWMxVan

Here is a BCM coding reference for the original Caddy equipped with Bi-Xenon and NSFW.
This may help you when comparing the coding.
Adresse 09: Zentralelektrik (J519) Labeldatei:. DRV\1K0-937-08x-09.clb
Teilenummer SW: 5K0 937 086 AA HW: 5K0 937 086 AA
Bauteil: BCM PQ35 M+ 122 0183
Revision: BD122001
Codierung: 611A583A8825086D088000809000096C0305000842008060E48487000041
davoc220
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Re: Xenon retrofit MK4 caddy

Post by davoc220 »

Iv had no joy sorting my programming out, going to take it to a be specialist I know and get him to sort it along with a few other bits n pieces


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VWMxVan
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Re: Xenon retrofit MK4 caddy

Post by VWMxVan »

davoc220 wrote: Tue Sep 16, 2025 11:27 pm Iv had no joy sorting my programming out, going to take it to a be specialist I know and get him to sort it along with a few other bits n pieces


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Have you tried the codes suggested in this thread they've worked for me really well ive just got a sticky main beam shutter now but thats the unit itself rather than the coding.

Possibly if someone could check your BCM code see if its that ?
MK4 caddy pure grey, OZ ultraleggera, 6 speed box 140 ecu.
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davoc220
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Re: Xenon retrofit MK4 caddy

Post by davoc220 »

I have, for some reason I still have the bulb failure for side lights


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davoc220
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Re: Xenon retrofit MK4 caddy

Post by davoc220 »

Crisis averted, went back over the coding again and it worked, happy days, thanks for posting this guys


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Scotscad
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Re: Xenon retrofit MK4 caddy

Post by Scotscad »

Hi guys, im guessing sum of u have used obdeleven to code on a mk4. Can anyone help me as im struggling. Got headlights coming on and off with the handbrake and no drl’s when lights switched off.
davoc220
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Re: Xenon retrofit MK4 caddy

Post by davoc220 »

I’m away from home just now working mine all work, get everything in the off position tho which Iv never managed to figure out, but Drl’s, side Lights, dip and main all work, even on LED bulbs


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Scotscad
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Re: Xenon retrofit MK4 caddy

Post by Scotscad »

Hey VWMxVan what long coding did u end up using to get ur xenons all up and running fine?? I cant get my drl’s to work as normal yet they come on when i switch the lights on and as parking lights with the indicator stalk. Mine is a2018 mk4 startline but iv already got heated seats wired in and working on the bcm so looks like its the rite on for the job. Cheers
STP
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Re: Xenon retrofit MK4 caddy

Post by STP »

Here's a thing, the OEM DRLs are twin filament brake/tail bulbs. Do yours have double terminals on the bulbs for drl/sidelights? Since they only work on sidelights then it could be that single filament bulbs are fitted as the look doesn't change when switching on sidelights, they just change from the 21w filament (drl) to the 5w (sidelight) ones normally.

This is true on the MK3 and 3.5 but not sure about the MK4.
2015 SWB Van, 1.6 CR TDI with Cruise Control, Heated Mirrors, Highline Clocks & MFD, VW Hands Free Bluetooth, Electric Windows, Reversing Cameras, DPF Monitor, Thatcham Cat 2.

My build thread: White MK3 Facelift

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Scotscad
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Re: Xenon retrofit MK4 caddy

Post by Scotscad »

The drl’s are led on the mk4 xenons. As i said they work fine with side lights, headlights, main beam and parking light function. Just dont come on as drl’s. They even come on when i do an output test to drl’s. Go figure!
davoc220
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Re: Xenon retrofit MK4 caddy

Post by davoc220 »

Do they come on as drl in auto lights?


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VWMxVan
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Re: Xenon retrofit MK4 caddy

Post by VWMxVan »

Scotscad wrote: Mon Nov 03, 2025 9:43 pm Hey VWMxVan what long coding did u end up using to get ur xenons all up and running fine?? I cant get my drl’s to work as normal yet they come on when i switch the lights on and as parking lights with the indicator stalk. Mine is a2018 mk4 startline but iv already got heated seats wired in and working on the bcm so looks like its the rite on for the job. Cheers
Hi bud so I've used this code everything works as it should I did have an issue where I put the code in and it took a little while for the drl to activate for some reason.

Save your original code just in case.

491A0A3E8025E16A08880082904008 6C0385C208420080A0648487000045

I will jump on my laptop abit later aswell just to confirm that is the coding on vcds.

Hope that helps.
MK4 caddy pure grey, OZ ultraleggera, 6 speed box 140 ecu.
KTM 250 EXCF Six Days
MK3 Clio RS200 ( Meglio) 340bhp track orientated.
theoldseacaptain
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Re: Xenon retrofit MK4 caddy

Post by theoldseacaptain »

The Mk4 had two different headlights during their production run - early with a H4 bulb and later with 2 x H7 so the wiring will probably be different between the versions. The sidelights work differently between the versions.

Had you checked that both versions are plug and play and don't need a link wire or modification or different coding dependant on what you had originally?
Scotscad
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Re: Xenon retrofit MK4 caddy

Post by Scotscad »

I have retrofitted xenons to my 2018 mk4. It did have H4’s fitted to the standard headlights and everything worked as it should ie:-drl’s. Now with the xenons in the drl’s dont come on as they should but everything else works fine. The drl’s is the issue im having, sidelights work fine. Thanks for the code VWM, will give it a try later on.
Scotscad
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Posts: 179
Joined: Wed Sep 04, 2024 12:23 pm
Engine size/power: 2.0 CR TDI (108bhp)

Re: Xenon retrofit MK4 caddy

Post by Scotscad »

I dont have auto lights davoc. Just poverty spec switch.
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