Golf 7.5 LCD digital instrument replacement - advice appreciated

[DonDubber]

My 2018 Alltrack has some apparently minor pixel deadspots in the instrument LCD screen display (part 5G1920791A).
I'm thinking of maybe replacing it sometime with either a genuine identical complete new unit (AliExpress approx $1600 ), or a used unit locally if I can find one which is better than mine (risky?)
However, I'm not sure of what coding would be required to match the new unit with the car, would this be VW Dealer only? I have OBD Eleven Pro, but I think it would need ODIS access?
Also, is coding any easier for a brand new unit rather than a used one?
Advice from our resident electronic/coding gurus re best option/s would be greatly appreciated!
TIA, Don Dubber

[Lucas_R]

These guys are based in Sydney and can do the coding for the virtual dash: VCDS - Vehicle Coding and Diagnostics Sydney

Unless one of the electronics gurus on here offers to do it for a fee.......

[DonDubber]

Thanks Lucas, looks like they know their VAG electrics stuff. But not clear whether only VCDS is needed, or is ODIS required?

[DV52]

Don:Hi.

Maybe another perspective might be of interest?

Before you throw money at this problem - it's important to understand that changing the instrument cluster (the module is called "J285" in the VW wiring diagram) on a MQB platform car is definitely NOT a trivial exercise from a coding perspective.

Issues that need to be resolved when J285 is replaced into a car post factory build include:

1. Component Protection: CP is a kind-of license that authorizes the module to operate for a particular VIN. When a replacement J285 (new, or 2nd hand) is installed into a post factory build car, a new license must be created for the retrofitted module. This process requires remote access to VW's central server - called FAZIT. In Australia, only dealers have FAZIT access
2. Immobilizer: MQB platform cars use 5th generation immobilizer which is part of an insert in J285. So, if a replacement J285 module is used, keying must be re-established. 5th generation immobilizer changes again need access to FAZIT
3. Odometer reading: Changes to the odometer reading on this car are severely restricted and they depend on whether the retrofit module is new, or 2nd-hand. But, the allowable options are limited!

So, moral of the story (IMO, of course): It doesn't matter whether you source a new, or second-hand module - it will be far easier if at all possible to repair the existing J285 than to replace the module.

Don
PS: I am aware that third-party providers sell a non-OEM replacement screen. The screen is sold by Alliexpress. I always have problems providing links to Alliexpress/eBay on this forum - so goto AliExpress and search for item 1005004055038838. Note the unit in my link is designed for a J285 module with mechanical clocks - I'm not sure if there is an option for an Active Info Display (AID) cockpit!

[Lucas_R]

Thanks Lucas, looks like they know their VAG electrics stuff. But not clear whether only VCDS is needed, or is ODIS required?

As far as I am aware, ODIS is required for when replacing the dash cluster due to immobiliser coding, and having to transfer over details from the old cluster (km's travelled etc). This cannot be done to my knowledge with VCDS.

[DonDubber]

Thanks DV52 & Lucas_R for your assistance. I'll have a look at the replacement screen option as a simpler solution. I have seen some on AE which supposedly are direct replacements for the factory AID screen. Apparently the screen part/version number for my car (& all Aussie Golf 7.5's) is LPM123G218A.

[DV52]

Thanks DV52 & Lucas_R for your assistance. I'll have a look at the replacement screen option as a simpler solution. I have seen some on AE which supposedly are direct replacements for the factory AID screen. Apparently the screen part/version number for my car (& all Aussie Golf 7.5's) is LPM123G218A.

Don: another matter not yet discussed about this exercise is the curious habit on MQB platform cars where the long-code string on the Brake module (@ address hex03) is often lost when J285 is disconnected.

I have never understood why this happens, but forums are littered with examples where the problem has occurred. When this does occur, lots of other modules spit-the-dummy in sympathy (because data from the 03 module is used by many modules on the CAN network)

It's not difficult to re-establish the lost information on the 03 module after J285 is retrofitted -but this is ONLY possible, if you have copy of the long-code string (the long-code on the 03 module is likely to be very long - 30 x Bytes)

So, my suggestion is to MAKE SURE that you take a FULL scan of the complete information about ALL modules on this car before you start the project

Don
PS: Even after you manage to correctly re-code the 03 module, it's highly likely that a number of calibration procedures will need to be completed (like the steering angle, and other sensors)

[kamold]

You can't replace with a used cluster unless it's by a dealer here.
VW will no longer allow used immo master components to be adapted, unless you get written approval (takes ~48 hours so you would have to leave your car there for a few days) which you can only get from a dealer in Aus.
You can swap just the LCD screen itself though which is easier and far less messing around than replacing the whole thing (apart from having to pull things apart, but it's very straight forward.)

[DV52]

@kamold: Many years ago, I became aware of a push by independent workshops in Australia with ACCC to test VW's monopoly regarding FAZIT access. As you will be aware, the situation in Australia is not replicated in some other countries - what happen to this initiative?

Don

[DonDubber]

Guys, thanks for all your extra info above, seems to be a bit of a nest of snakes to play with this
Don, is fitting a replacement LCD screen to the original J285 likely to cause Brake Module issues? I have previously had the car battery disconnected for several days continuously when fitting/wiring front & rear dash cams, and all J285 fault lights (steering, ACC, parking sensors, etc) when reconnecting the battery thankfully disappeared after a 1km drive around the block several times. I then was able to use OBDeleven to easily clear the stored fault codes as well, with no continuing issues.

[kamold]

Yeah we are really punished by not having proper right to repair laws here.
I would happily pay for proper access. I have enquired multiple times to VW Aus and always had zero reply.

[kamold]

Replacing the LCD will cause zero issues. It has no coding or CP. It's just a display.

[DV52]

Don, is fitting a replacement LCD screen to the original J285 likely to cause Brake Module issues? I have previously had the car battery disconnected for several days continuously when fitting/wiring front & rear dash cams, and all J285 fault lights (steering, ACC, parking sensors, etc) when reconnecting the battery thankfully disappeared after a 1km drive around the block several times. I then was able to use OBDeleven to easily clear the stored fault codes as well, with no continuing issues.

Removing the battery leads is not the issue - as I say, I have NO idea why it sometimes happens. I would be embolden by @ Kamold advice below:

Replacing the LCD will cause zero issues. It has no coding or CP. It's just a display.

Nevertheless, for added security and because it's an easy task, make sure that you have a copy of an up-to-date SCAN that shows the module long-code strings. (VCDS scans does this as default - but if you are using OBD11, you need to enable the freeze-frame data option)

Don

[DonDubber]

Thanks guys for the further advice above, and yes I'll do a backup scan with OBDeleven before I start any disassembly. Should I also disconnect battery?
I've located a supposedly identical replacement screen on AE (404 page) for about $270 delivered in OZ, with a free return possible if I chicken out at the last moment

[DonDubber]

PS: the AE reference is: 404 page (apparently my copy & paste directly from AE site doesn't work)