Backstory

I bought a new (to me) car! Oh the joys of new car ownership. You get to find all the things that were or weren’t done right from the previous owner. In my case, my new to me car was a relatively well maintained Audi SQ5 2019 with 87k miles on it.One thing that I had to fix was the water pump on this car. That was a whole thing because Audi wanted like $4k to fix all the things from that TSB. I decided to do that one myself, with my brothers help, of course.I will note, the reason I found this out was doing a oil test with Blackstone Labs, a wonderful $40 test that helps save a lot of time and potential money to see if there’s anything wrong with cars, but again, side note.In doing so, I had to take the front bumper off. Little did I know that removing a bumper requires a recalibration of the front ACC sensors. Once my brother put everything together he found out that the light came on and ACC wouldn’t work. Not even basic cruise control, which was a frustration as someone who came from basic cruse control, I knew how to operate the brake, but guess Audi had enough cases that people assume it would stop for them that they had to remove that feature.I then found out the only people who could do that is (whaddayaknow) Audi. I could not find a shop that would do ACC alignment.I decided to shell out the $600 to take it to my local Audi dealership. I already had a rough history with them since they had messed up EVERY. SINGLE. REPAIR. I had them work on. So was already pretty wary taking it to them to get this repaired.I took it in, and they completed both the mechanical and ACC alignment for me.After that was complete, I took it for a drive, and about 1,000 miles later the ACC failed again. So much for spending $600 for them to do it right.After that experience, I gave up taking it to the dealer and decided to do some research. I read some reports that you could read the alignment values myself and fix it myself.Some reported you could do it with OBD11, and others with the VCDS tool by Ross-Tech.So thats what I did.

Fixing ACC Myself

I bought the VCDS HEX-V2 tool by Ross-Tech.Following some online guides for cars that were different/older than my car, I was able to get close to understanding what I needed to do.I plugged up the VCDS tool, and opened the app and read the codes.Mine was showing ACC Sensor 1, Address 13 (passenger side) was misaligned.Here’s where I thought I had to break out my technical coding and such and start typing in security codes, blah blah blah to get to reset the codes as the guide I was following showed.The guide stated that I had to enter the security code to reset the values, and with much faffing I found the right code (20103 and 14117). Both seemed to work, can't remember which one was for which, but found out I didn't really need them at all.I loaded the following values in from their selector list for that sensor:

• Mirror deviation: horizontal
• Mirror deviation: vertical
• Misalignment angle: horiz
• Misalignment angle: horiz fast algorithm
• Performed adjustment-Horizontal offset angle
• Performed adjustment-Vertical offset angle
• Vertical deadjustment

The only one I really needed was misalignment angle: horiz, misalignment angle: horiz fast algorithm, and vertical deadjustment. For me, those were the ones that were off.I noticed they were the ones that at least looked like they should be between the .80 value shown in the forums.

On the front of the car, I took off the grill by just pulling on it, then pivoting on the inside bumper plastic tags (near the inside of the car)and it exposed the alignment screws for the sensor.This is where my trial and error kicked in, and it was a bit fuzzy but if I remember correctly:

• Upper left screw - Horizontal - tighten is right (negative value on the VCDS reading), loosen is left (positive value on the VCDS reading)
• Lower right screw - Vertical - tighten is up (positive value on the VCDS reading), loosen is down (negative value on the VCDS reading).

These were fuzzy checks so don't quote me on these.After I twisted them a couple turns with a 10mm Torx bit, I went for a drive, and monitored the numbers, if they went down, I figured I was going the right way, if they (sorta) stabilized I figured they were getting close to the actual value it had determined.I did have to drive in relatively heavy traffic for it to start changing and locking in a number.After about 20 minutes of driving, it was settling and still show the error ACC Not Available. I saw either Vertical deadjustment or Misalignment angle: horiz fast algorithm still showing above the .8 target value.I tweaked the screws a little more depending on which one was still showing off then went for another drive, careful not to overdo it because then the value could swing wildly the other direction.After a while driving the ACC error just resolved itself, and let me turn cruse control on again.Both vertical deadjustment and Misalignment angle: horiz fast algorithm are both inside the .8 degrees value.

I've driven another 1,000 miles with no further issues.Now, don't know if this is the "correct" way or if there are other gotchas, but for me, I just wanted cruse control back, and now I have it back and it's working fine, and I didn't have to pay another $600 to Audi who clearly couldn't do it right in the first place.