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Old October 29th, 2019, 16:42   #8
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Join Date: Feb 2005
Location: Island near Vancouver

LRR (Long Range Radar) Installation:
My car (2015 GSW) came with "Front Assist" already installed, with the hardware being the MRR (medium-range), which is flat-faced; it functioned to simply scream at me if I was approaching something too quickly, and the opportunity to stop was quickly diminishing.

But, no autonomous braking (that I was aware of), and no ability to re-code this to work with ACC.

With the MRR installed, it's just held by three knobbed pins that pop into rubber sockets on a mounting bracket. The mounting bracket is secured by two 10mm bolts. You can either simply pull the MRR directly out (possibly bending the bracket if it doesn't let go easily), or unscrew the 10mm bolts. First time I did it, I took off the bumper cover, but subsequently, I just removed the license plate and its own plastic mounting piece, and un-did the bolts. Don't drop them, otherwise you might be pulling off the bumper cover. Wiring harness at the front radar needs no modification.
This is what the LRR looks like installed (not on my car):

MRR (with bumper off):

Mounting pins:

ABS Wheel sensors installation:
Only the rear wheel sensors are replaced. Same part number for both sides. One 5mm allen-head bolt holds them in. If you ever replaced the ABS sensors....this is nothing like those. A little pushing and wiggling and they come out. Easy-peasy.
Grey - new ones; black = OEM

Coding (particularly the ABS module):
A couple of basics to get out of the way.
First of all, when you install a new (as in different) ABS module, your ABS coding becomes 30 bytes worth of zeroes, and your old coding will not work.
If you want to “trial-and-error” your way through 30bytes, there are roughly 4.2x10^23 permutations (or a few billions of billions of years worth, if you could try one per second). So, you probably don't want to go that route.

Each byte is represented by eight bits, each of which can either be on/yes (1) or off/no (0).

Each byte, then, can be viewed in VCDS’s Long Coding Helper as eight digits, each digit being a 0 or 1. The eight bits are number 0-7.

Now, the confusing part: bit 7 is the left-most bit. Then 6-5-4-3-2-1-0 in sequence going rightward.

Thankfully, much smarter people than I figured stuff out, and user Somnus over at Ross-Tech has put together this Google Sheet which provides his best guesses (based on some reviewing a lot of ABS codings) as to the function of each byte and corresponding values.

Note: As pointed out by Somnus, you're on your own here; the information provided is merely some educated guesses. I'll offer what worked on my car, but if you decide to try this and follow what I did and it totally bricks your car...that's on you.

So, the good news is that the first 22 bytes (Byte0 to Byte21, inclusive) should line up fairly closely with what you had in your OEM ABS coding. Many of the bytes are related to the last six digits of your VIN, and the binary inverse of those.
Non-pro tip: If, like me, you barely understand bits and bytes and converting, get yourself a spreadsheet and get comfortable with these two formulas:
"cell" is the cell that has the value you want to convert; the "8" in the second formula ensures that you see all eight ones/zeroes)
There's a .pdf floating around out there by "Xagico" that lists a pile of different retrofits and mods that can be done on the Mk7; it has a lot of the coding changes to be made. So that's where I started.

In ABS coding, however, the recommendations on Byte24 (F4 or F8) were not accepted by my car. (I'm guessing this is because Xagico is Spanish(?), and the European cars came with some hardware as standard that were not offered on our cars).
Anyway, using the Somnus's spreadsheet, I was able to calculate that Byte24 on my car should be either 16 or 18; I tried 16 there and it worked. Again, YMMV, so do the math for yourself.

Next, I changed Byte26 to F0 - if you install the new rear wheel ABS sensors first and continue to drive your car without making any other changes, you'll probably have a pile of errors on your display. Change this byte and the errors should disappear literally as you're sitting there.
(Xagico's pdf said to change this to 50, and when I had my just the wheel sensors in my car - without swapping the ABS module - "50" made the errors go away. But once the new module was in the car, while I didn't have any errors, ACC would not work. Helpful user at ross-tech forum suggested to try "F0"....and just like that, everything, ACC worked. Not sure how he arrived at F0, but I'm glad he did.

Lastly in Byte29, Xagico said to change it to 39, but that didn't work for me. A user over at Ross-tech's forums helping me out suggested 22 - and that one worked.

Bleeding Brakes / ABS:
This one had me stumped for a while because I couldn't get it to work in ABS (it's nothing like in the old Mk4 where you just go to BASIC SETTINGS in 03-ABS and hit GO and it tells you what to do. There are things that look like what I need to do (e.g., Fill/Bleed Brake System),

but it asked for inputs (a one- to three-digit number) and nothing I tried for an input worked.

So, I made my first real use of ODIS - and if you've never used ODIS before, send a letter of thanks to Uwe and the guys at Ross-Tech. It is SO cumbersome and slow. Even the techs at my local VW dealership like VCDS better because of how quick and concise it is.

Anyway, ABS BASIC SETTINGS in ODIS guided me through the ABS cycling, brake bleeding, etc.

Clearing Errors:
Even after you get the ABS coding figure out, you're still going to have a pile of errors (e.g. ESC, tire pressure monitoring, etc.)
Usually, I'd just take the car for a drive, make sure the steering wheel gets moved all the way right/left, and it all resets itself.
Not this time.

In ODIS, I had to do BASIC SETTINGS in the module 44 - Electric Steering Assist. Basically, the car needs to re-learn where centre is. You put the SW at exact centre, then follow prompts to turn all the way to the right, all the way to the left, then back to centre. Can't remember the exact process, but ODIS is fairly hand-holdy, so it makes sense.

And literally, as soon as that was set, the errors just immediately disappeared from the cluster and infotainment unit.

I think that about wraps it up. I'll update if anything else springs to mind, and answer questions best I can.

His ride: 2015 GSW SEL TDI with MIB2, Active Info Display, Adaptive Cruise retrofit
Her ride: 2016 A3 e-tron

His other ride: 2015 Giant Propel SL Di2

Last edited by Nuje; November 1st, 2019 at 09:22.
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