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7.5R Tailights -> 7.5 GTI - Coding help please!

jack.dd2mw

New member
Location
Australia
Car(s)
Mk7.5 GTI
Hi there, would anyone be able to lend me some help with coding some taillights I have swapped in.

I'm from Australia so the talk between Euro and NA differences are very confusing and I'm unsure if I need to install a harness...

I've taken some taillights off a wrecker 7.5 R and have put them on my Mk7.5 GTI but was wondering if I required a harness, and what coding I need to do to get everything working.

Here are my current issues:
1. The two inner indicators (left & right) don't work at all
2. On the right side, the fog light and reverse light are swapped,
3. The fog and reverse light don't work at all on the left side...

Thanks for your help here!
 

DV52

Drag Racing Champion
Location
Australia
G'day cobber - Thanks for the PM!!

First question: Aussie mk7's normally are Rest-of-world (RoW) models, not EU. So, why do you mention "Euro and NA differences" in the context of this matter ? I can't imagine that you managed to find a NAR model 7.5R in an Australian wrecker yard. Or is your mk7.5 GTI sourced from USA, or Europe (is it left-hand drive)?

So, the important thing about changing the tails on a Golf mk7/mk7.5 is the number of wires in the car loom that connects the controlling module for the tail-lights to the plugs on the physical tail-light housings (there are 4 of these plugs -an inner and outer fitting on each car-side). Obviously, these wires were factory installed when the car was built -so they match the tail-light option that was delivered with the car when new.

The number of wires in this loom exactly matches the number of lamps in the tail-light housing and OEM fittings with incandescent lamps have fewer actual physical lamps than their LED equivalents. For example, incandescent tail-lights have only ONE set of turn-signal lamps whereas LED tails have turn-signals on both the inner and outer fittings on each car-side. So cars that are factory built with incandescent tail-lights will have fewer wires in the wiring loom than cars that were factory delivered with LED tails.

How was your mk7.5 GTI factory built? And do you own a diagnostic device - if so, what sort?

Don
 
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jack.dd2mw

New member
Location
Australia
Car(s)
Mk7.5 GTI
Hey Don, thanks for getting back to me and apologies for the confusion...

My car would be one of the RoW models then, and the same with the tails.
I previously had the LEDs but without the dynamic indicators as found on the performance pack GTI or R.

I've attached some screenshots of some online. The white car is what mine used to look like and the black one is what they are now.

I've got an OBD11 which I've been trying to figure out...

Thanks!
 

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DV52

Drag Racing Champion
Location
Australia
hmm......... bummer - I've not had much experience with those particular tail-lights (albeit they are very common)!!

So, you say that the inner turn-signal lamps don't work at all. I assume that the outer turn-signal lamps do operate - but do they operate in dynamic mode?
 

jack.dd2mw

New member
Location
Australia
Car(s)
Mk7.5 GTI
hmm......... bummer - I've not had much experience with those particular tail-lights (albeit they are very common)!!

So, you say that the inner turn-signal lamps don't work at all. I assume that the outer turn-signal lamps do operate - but do they operate in dynamic mode?
Dam... The outers do work, but not in the dynamic mode.

Would you recommend just doing some trail and error with each lamp adaptation?
 

ZERO815

Autocross Champion
Location
Köln Germany
Car(s)
2017 GTI SE DSG
There is nothing you can do with coding alone. It needs re-wiring or harness and coding to work properly.

There are basically 3 options for you:
1. Re-pin and add a couple of wires just between the 4 tail lights
2. Use the harness 5G0052400 that comes with the OEM retrofit kit. Here you have to run a single wire along the left rocker panel to the BCM under the dashboard
3. Get an adapter harness that plugs between the vehicle wiring and the new lights.

All 3 options require their own specific coding instructions. I can help you with all of them, just let me know what you prefer to do.

Most likely the lights that came with your car were not the MK7 LED of the white car picture. Those have 4-pin and 5-pin connectors instead of the facelift 8-pin connectors.
 

jack.dd2mw

New member
Location
Australia
Car(s)
Mk7.5 GTI
Thanks Zero,

Yep, it looks like it'll need re-wiring. Interestingly I do have the 8-pin connectors.

I've put some orders in for some more connectors & terminal pins and I'll grab some cables. Should be a fun project making a DIY harness.

I imagine I will require your coding instructions for option 1.

Cheers for your help!
 

ZERO815

Autocross Champion
Location
Köln Germany
Car(s)
2017 GTI SE DSG
To get the reverse lights and rear fog light working correctly all you have to do is:
1. Driver inner: Swap wires that are in Pin6 and Pin7
2. Passenger inner: move wire in Pin7 to Pin6.

Attached you‘ll find a DIY for LHD vehicles. The only difference to your RHD vehicle is the location of the rear fog light wire. In my instructions the yellow wire is shown on Inner-Left side while in your car it is on Inner-Right side. Everything else is the same. Does that make sense?
 

Attachments

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jack.dd2mw

New member
Location
Australia
Car(s)
Mk7.5 GTI
Yep thanks again!
I've swapped/moved the ones I have and the reverse lights are working great.

Will post an update when I get the other connectors & wires.

Also just to check, I only have to update three of the Leuchtes?

Cheers!
 

ZERO815

Autocross Champion
Location
Köln Germany
Car(s)
2017 GTI SE DSG
That’s correct ✅
 

jack.dd2mw

New member
Location
Australia
Car(s)
Mk7.5 GTI
Thanks Zero, I've got it working now (and for a lot cheaper! - at least in Australia)

Just for anyone looking to do this in future - for left hand drive cars:

Use the left reverse pin (blue/black) as the dynamic control pin (goes to pin 1 for all connectors).
Otherwise, the reverse camera will flip out only when indicating

Then use the right reverse pin to run both reverse lights.

Also note that there is only 1 rear fog light (on the right).
 
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