ACC = Adaptive Cruise Control

[roguester]

Hello all,

Very new member here, so please be gentle. In need of some help/advice/assistance etc with my ACC.

I recently purchased this car, a big buying factor was the ACC. If you have had it before you will get spoilt, especially with highway driving!!

In a nutshell - mine has moments where it does not detect the car in front and will near rear-end -> the front assist intervenes - almost as quickly as my hovering right foot. Other times it is smooth sailing and works well.

I have been to the dealer and they reported that there are no error codes being produced and recommended a re-calibration at an eye watering price close to $1.6K which, 'may or may not fix the problem', but could prompt the system to bring up an error code to address the issue.

Thank you in advance for your input and time.

Pete

[MIG]

Welcome, Pete,

You got the 3.6 with all the bells and whistles, nice!

$1.6k for a radar alignment What is the book time on that? That's crazy. Many shops do ADAS calibrations now, so don't think the dealer is the only place that it can be done.

One thing to check is the front badge; it's not unheard of for a large stone chip or cracks to form in the ceramic material, allowing water in and interfering with the radar signal.


With this issue, does it happen more when cars are moving in front or when stopped?

[roguester]

Thank you for the reply MIG!

Don't get me started on the cost of things.... sagging sun roof blind replacement - part and install is $2,524 - Blind will be left open at this stage! I have seen the blind on ebay for $135. No idea how to remove a roof to repair so will leave it alone currently. It will get to me eventually lol. They said they need the car all day to do the recalibration.

As for the ACC - ive flicked it on and its not detected cars despite being 10m in front of me moving. Just the outside lines to the left and right. Then a car will fly past me and it will detect it and bring up that little bold car picture. It seems to do that a lot when its working so not sure if that's what it is meant to do, bringing up the picture of the car in front every time it detects or sees one moving with that flat bit under it that goes up and down closer and further away. It is hard to explain.

If I am stopped and flick it on it brings up a 'speed' something alert on the display. I am used to the car bringing itself to a stop and when traffic starts moving the ACC will start moving again - not sure if this system does this.

I was unsure what the ADAS calibration was - I thought it was more for the front assist when you change windscreens? The LKA works well which is one positive. I had a look at the front VW and there was nothing obvious just some slight wear to the outside edges if anything.

Pete

[MIG]

These days, ADAS is almost any external sensor; many companies make tools that work with various car brands and techs, including ACC, blind spot, LKA, etc.

A good place to ask is crash repair places; they generally have the tools (Hunter), as any minor front-end collisions on modern cars need recalibration, and as you saw with the dealer, I would imagine them justifying the hardware and training

If you are game(or want to do things yourself), you can test the current alignment by removing the front grill and using a laser pointer \ laser level to check against the guide mirror that is part of the radar module. The mirror is normally used to get the radar close to centred to allow the calibration procedure to run via a scan tool, But it should give you a general idea if it's way out.

The 'speed' warning is normal; the system needs to be active while moving, and after it's on, it can slow to a stop.

[roguester]

Thank you! I will reach out to a few ADAS places and see what they can do/offer.

If it was an alignment issue would it intermittently work? If for argument sake, the radar was not getting power (or faulty) would it bring up an error? Would it still engage cruise control? I was whinging to my mother and she suggested an auto electrician?

I don't mind getting my hands a bit dirty, though my skills and expertise is limited (translated to I don't want to break anything LOL).
In terms of scan tools I do have a cheap and nasty bluetooth tool would that be able to see if any codes are being produced by the system? If you can recommend any I don't mind forking out a bit of dosh.

Pete

[MIG]

Alignment and interference can cause weird things, such as phantom braking, seeing cars in other lanes, etc. I had those issues when I first installed the radar on my car. I was using the non-acc badge while I waited for the correct one to arrive.

If the unit had an internal fault or was dropping power, the ECU, ABS, and ACC modules would log faults; getting (or borrowing) a scan tool that can talk to VW modules, VCDS, OBD11, etc., might be a good idea, as who knows if the dealer just wanted to sell an alignment before hardware replacement, lol.

[roguester]

Thank you for your reply! Ok then, I might also replace the badge just for peace of mind (and to rule out one possible issue). Would you have the part number handy at all?

That is the problem with the dealers and as much as I take things at good faith, I would like to see it with my own eyes also they are very quick to push you out the door once the car is dropped off. Not that I am a voyeur, though I would like to hang about watch and learn something also.

Sadly, I don't really know anyone with a scan tool, so will best purchase one for myself they do come in handy at some point. I was planning on taking the car for a run somewhere today she doesn't get much of a drive during the week as I walk to work and everything in close by.

[kamold]

Firstly just check that the radar is properly mounted in the bracket.
Years ago I helped a colleague who had had his B7 into VW for 'calibration' and was still having issues.
Found the radar wasn't attached to all 3 mounting points...

[roguester]

Thanks Kamold,

I went down and had a look through the grill, I can see 2 bolts on the drivers side of the unit. The other side is not easy to visualise.

I went hunting and found my cheap universal bluetooth scanner and plugged it in. Have put a bid on an OBDEleven on ebay.

Under No. 13 Active Cruise Control
00532
Supply voltage
Status: Pending fault present during this driving cycle, Validated and stored in non volatile memory.

[kamold]

That fault just says low voltage.
Start the car and clear the fault. Won't affect calibration.
You need to pull the centre grill out at the top so you can then pop the badge out and get access to the radar and mount.