Active Cruise Control - Details and Photos

[PanEuropean]

Hello All:

I was in Dresden last week, doing some research about a Phaeton that I plan to order through my dealer in Canada. I took some pictures of a Phaeton that has the Active Cruise Control (adaptive distance control) installed. This is available on the MY 2005 Phaetons in Canada, but it is listed as a 'delayed introduction' option - not sure what this means, perhaps it won't be available right away.

I did not see any 2005 North American Phaetons with this option installed, but when I did the tour of the assembly facility, I saw a 2006 North American Phaeton that did have this feature installed. The photos below are of a 2005 European vehicle - one of the fleet kept at the Dresden factory to show buyers the different vehicle colours, interiors, etc. This option is listed in the 2005 German price list at € 2.380,-

The radar transmitter/reciever is located on the passenger side of the front of the car, just below and outboard of the licence plate. You can see the slightly different front foglight bezel (the black area is radar-transparent) in the photo below. There are photos of the actual component that is behind the bezel towards the bottom of this thread.

Front Bumper, showing transmitter - receiver for ACC

The control is on the left side of the steering wheel. The small thumbwheel on the left allows you to adjust the time interval (in seconds) between your car and the car ahead of you. It regulates time, not distance, so it adjusts the distance according to the speed of the two vehicles. The buttons marked GRA+ and GRA- mean "Gradation" - pressing either button increments the speed up or down by 10 km/h (6.3 MPH).

Steering Wheel, with controls for ACC

I do not know if the North American implementation (functionality) of this will be the same as the European implementation.

Michael

[PanEuropean]

Here's a bit more information about the ADR system. The source of the text and photos is a press release from VW (posted at German Car Fans .com), dated November of 2002. I believe that ADR will be available quite soon (perhaps in the next 90 days) as an option for North American cars. I'm not sure if it can be retrofitted to an existing car by an enthusiast or not, but eventually I will try to find out.

The innovative Automatic Distance Regulation (ADR) system uses radar to detect vehicles ahead

Speed and distance controlled with the left thumb

Optional ADR adds an automatic braking and accelerating function to the standard cruise control

ADR makes the journey far more relaxed: the driver senses directly that the car is performing various dynamic driving processes itself

Wolfsburg. The Volkswagen Phaeton is one of the most innovative luxury saloon cars available anywhere in the world. Technical highlights such as its 4-zone Climatronic air conditioning, air suspension with controlled damping and the progressive Automatic Distance Regulation (ADR) system, an optional extra, set the standards in this automobile-market segment. This applies to ADR in particular: it transforms the previous style of travel into a new dimension of relaxed convenience. More than was ever possible until now, the driver can sense how the car is performing various dynamic processes on its own initiative.

The automatic distance regulating system uses radar, and takes over precisely where the conventional cruise control (GRA, standard on the Phaeton) calls for the driver to take action: when the car has to be braked or accelerated. If a Phaeton equipped with ADR approaches the vehicle ahead too closely because this is being braked or simply driven more slowly, Volkswagen’s new luxury saloon model reduces its own speed automatically by the necessary amount. The driver sees a signal on the central information display between the speedometer and the revolution counter as an indication that this regulating process is in progress. If the preceding vehicle then speeds up again or the Phaeton’s driver changes to an empty traffic lane, the system accelerates the car automatically back up to the previously selected cruising speed.

Self-explanatory controls on the multifunctional steering wheel

The ADR controls have been designed for exceptional ease of operation and reliability, and are self-explanatory. All the main controls are on the multifunctional steering wheel, which is a standard equipment item. An ‘ON/OFF’ switch activates the ADR and a ‘SET’ button accepts the speed at which the car is travelling as the desired cruising speed. The central information display in front of the driver then shows a stylised section of road with a virtual preceding vehicle and an icon to indicate the system’s functional status. The speed can be varied by the cruise control buttons on the steering wheel.

An innovation has been introduced here too: on conventional systems the car first has to be accelerated with the pedal or by holding the ‘SET’ lever until the desired cruising speed is reached. This method can be adopted by the Phaeton’s driver, but it can also select the desired road speed in 10-km/h steps, up to a limit of 180 km/h. The speed selected but not yet reached is marked on the speedometer dial by a red light-emitting diode above the numerals on the scale and shown on the information display.

The ADR’s distance margin and response dynamic can be varied individually

Within predetermined ranges the driver can also vary the minimum distance from the vehicle ahead and the dynamic response of the ADR system. A drum-type switch on the multifunctional steering wheel selects one of a maximum of seven positions, which are shown graphically on the information display. The settings 1 to 7 represent the elapsed time before the Phaeton reacts to the presence of a preceding vehicle. In position 1 the Phaeton is braked later and, when the road is clear, accelerates more rapidly. In position 7 it brakes very early and accelerates less rapidly.

Settings 1 to 5 are intended for normal driving on dedicated highways; the Phaeton then responds in accordance with the traffic flow and accelerates briskly at the rate the driver prefers when it is steered into a free lane. For long journeys on motorways or similar main roads, settings 3 and 4 are ideal. The last two settings (6 and 7) are intended primarily for ordinary main roads. In setting 7, the distance to the vehicle in front in metres corresponds to the Phaeton’s speed in kilometres an hour: 100 km/h are equivalent to a gap of 100 metres. This setting makes overland journeys very relaxed. If urgent action on the driver’s part nevertheless becomes necessary (for instance if a panic brake application is made), the system provides an audible and visual warning.

The radar system scans the road continuously for 180 metres ahead of the car

Within an angle of 11.5 degrees and for a distance of approximately 180 metres, the ADR detects all vehicles moving in the same direction. The system can be activated at any road speed between 30 and 180 km/h. Above and below this speed range the ADR is de-activated as a safety precaution. The driver can also switch the ADR off by pressing the brake pedal or using the ‘CANCEL’ switch on the steering wheel. If the ‘RES’ (‘RESUME’) button is pressed later during the same journey, the automatic mode and the previously memorised settings are restored.

The complete Automatic Distance Regulation system consists of the ADR control unit in the radar sensor housing, an active brake booster servo (BKV) and the servo control unit. The radar sensor at the front of the car transmits signals in the 76 to 77 GHz range. Since the system is networked with the ESP, it is supplied with information on the Phaeton’s road speed and yaw rate and uses these parameters as well when determining the desired speed change.

The system is networked by means of the driveline CAN bus, so that the ideal engine torque can be sensed. The CAN bus line is also used to link it to the control units for the active brake booster servo and the automatic transmission, and to the central instrument cluster in front of the driver. The ‘Comfort’ CAN, the CAN gateway in the instrument cluster and the driveline CAN are used to connect the controls on the multifunctional steering wheel to the ADR control unit.

ADR optimises journey refinement

Naturally the ADR does not absolve the driver from the responsibility of concentrating on the traffic flow and reacting defensively. What it does is to support the driver in responding particularly effectively to changes in the traffic pattern. Automatic distance regulation helps to avoid driving too close to the vehicle in front in all normal traffic situations and warns the driver whenever action has to be taken. These features of the system can only be regarded as a fundamental step forward in personal driving safety, comparable to the ESP which also helps to prevent accidents from occurring in extreme situations. ADR automatically promotes a defensive style of driving and prompt responses when called for.

-30-

[Docroger]

My wife's Toyota Sienna minivan has this feature; it is really neat to use and I miss it in my Phaeton after I've been driving her Sienna. Of course, that's the only thing I miss about the Sienna (although it is a fine minivan).

Incidentally, that front photo is of a MY2004 grille? I wonder if the Laser cruise control in fact made it into some European Phaetons.

[PanEuropean]

Doc Roger:

That is a 2005 European spec car. All of the photos of cars that I have posted over the last two weeks (unless otherwise attributed) were taken at the factory in Dresden during the last 2 days of September and the first 2 days of October this year. The cars that are shown outside are part of the fleet of cars kept at the factory to allow buyers to compare different colours, interiors, etc.

Cars have been shipping in Europe with the active cruise control (ACC) for quite some time now - I think since the beginning of this year, perhaps longer. Mercedes has been shipping cars in Europe with a similar but less sophisticated ACC system for at least 2 years now.

You can tell the difference between the 2004 and 2005 short wheelbase Phaetons by looking at the top horizontal surface of the grille. On the 2005 short wheelbase models, the top horizontal strip is wider than the bottom horizontal strip. 2005 long wheelbase models (the only kind we get in North America) have an entirely different grille. Photos of all three grilles, and additional text, can be found at this thread: http://forums.vwvortex.com/zerothread?id=1621457

PanEuropean

[vwguild]

I am still having a tough time understanding the purpose of this feature...

[Docroger]

Once you drive it VWGuild, you'll get it (does that sound familiar)? You set the cruise control to a desired speed, and it functions just like "regular" cruise control until you come up behind another vehicle. Then, the Laser bounces off of the car in front of you and your vehicle slows to keep a specified distance between you and the vehicle in front of you. If the vehicle in front of you leaves your lane or speeds up, your car will speed up again to the maximum speed that you have set.

It's a little eery at first, particularly the automatic braking, but you'll quickly get used to it. It really works nicely. In rain, however, the system will not operate (at least in my wife's Toyo) as the Laser gets fooled as it bounces off of the raindrops.

[PanEuropean]

VW Guild:

It is a cruise control that is aware of other vehicles that are in front of your vehicle. It will slow your vehicle down from its set speed - either by reducing engine power, or by applying the brakes if necessary, if you get too close to another vehicle.

Once the obstructing vehicle has accelerated or moved out of the way, your vehicle will then accelerate to the originally set cruising speed.

This option will soon appear in North America. It is listed as a 'delayed introduction'. The delay was caused by California motorists, who want a TOW missile launcher incorporated into the system, in case the obstructing vehicle remains in their way for longer than 5 to 7 seconds.

PanEuropean

PS to Doc Roger: I believe that in the VW implementation of this, radar (radio waves) are used for the distance measurement, rather than laser (light waves).

[4x4s]

Quote, originally posted by PanEuropean »

The delay was caused by California motorists, who want a TOW missile launcher incorporated into the system, in case the obstructing vehicle remains in their way for longer than 5 to 7 seconds.

Ooo! Do you think VW will offer that on the Touareg too? I want one!.

[vwguild]

Guys....I understand what it is supposed to do...I just don't understand
why anyone would use it...Sounds kind of George Jetson to me...

Travelling @ 80+ on 101...I don't think so...I try to keep at least 6-7 car
lengths between me and what is in front...lots of room to slow down because of the morons behind that tailgate...

[PanEuropean]

Quote, originally posted by vwguild »

...I just don't understand why anyone would use it...

Your doubts are quite understandable, considering how motorists normally drive in North America.

In Europe, drivers maintain very tight spacing between their vehicle and the vehicle in front of them. Two or three car lengths - maximum - is considered more than enough when travelling on autobahns at average speeds in excess of 100 MPH. Even in the fast lane, where sustained speeds often hit 150 MPH, you won't ever see more than about 5 car lengths between vehicles. In the city, you won't see more than a one or two car length gap in moving traffic. A person is not considered to be 'tailgating' (crawling up your butt and suggesting you move out of the way, or move faster) until you can't see the grille of their car in your rear view mirror. If you do see that in your rear-view mirror, your first reaction is "Geez, I'd better speed up or get out of the way", not "I'll show him who's boss by slowing down or hitting my brakes."

In light of this, a system that automatically maintains a fixed distance between you and the car ahead is a very useful device. It reduces driver workload and enables the driver to maintain higher overall situational awareness.

North American drivers are taught to maintain a much bigger space between vehicles. As a result, fewer cars per unit of time traverse the same section of roadway, and we get traffic jams and longer travel times. I really don't think the ADC will be useful as a 'cruising' device in North America - probably its main value here will be helping to avoid collisions with the car ahead that are caused by the driver of the (ADC equipped) car not paying enough attention, perhaps due to cell phone distractions, etc.

In Switzerland, the minimum classroom training time and in-car dual instruction training time requirements to get a basic driver license are higher than the American classroom training time and in-aircraft dual instruction time requirements to get an aircraft pilot license. As a result, a lower % of the population drives - those who don't have the intellectual competence, physical co-ordination or spatial awareness skills to drive competently just don't get past the dual instruction period, let alone get a chance to attempt a driver license test.

PanEuropean

[PanEuropean]

VWGuild:

I just discovered that the purpose and operation of the ADC function is fully described in the Phaeton Owner's Manual, book 3.1.1, "Controls and Equipment, General Information", September 2003 edition, on pages 130 and 131.

PanEuropean

[vwguild]

I know. it has always been there...It is just not something that I would ever use...I don't even mess with Cruise Control...Never know what to do with my right foot, and I like being in total control and having that feeling of attachment with the car...

[PanEuropean]

Here's a link to a QuickTime movie that shows the Active Cruise Control (ADR) in use on the autobahn in Germany. The voiceover is in German, but the pictures are in English. Note how closely spaced the 3 Phaetons are, even though they are moving at very high speeds.

ADR Movie
Click on the image below to watch the movie. The narration is in German.

[PanEuropean]

The staff in Dresden told me today that they have built Phaetons for the North American Region (NAR) with active cruise control installed, so the 'delayed introduction' of this feature to NAR is no more - it is now available. My guess, though, is that you would have to special order a Phaeton to get this option, I kind of doubt that VW would just install it for the heck of it on a car destined for 'dealer stock'.

Michael

[DCubed]

Michael

This option code never hit the 2005 Order guide, and they might have been assembled for VWoA "tester" cars, because it is not in the 2006 order guide as well, so we will see if its a mid year running change for 06.

Derek

[chrisj428]

Quote, originally posted by PanEuropean »

I'm not sure if it can be retrofitted to an existing car by an enthusiast or not, but eventually I will try to find out.

Michael, I'm going to have to say "no" (as much as it saddens me). Not only would you replace the controls on the steering wheel, add the control module and sensors for the ACC; the ABS control module would need to be replaced (The ACC module is slave to the ABS module, otherwise you would have unprotected (eg: outside the vehicle) CAN-BUS access, making the car about as easy to steal as if you'd left a key in the ignition), you would also need to replace the brake booster, as the regular one doesn't have the electronic controls to apply braking force as required.

I'm thinking the costs would be astronomical -- better to take a depreciation hit & buy a new one.

[dzier]

My 04 Toyota Sienna minivan has laser distance cruise control. It works well, but is annoying. You better try before you buy!!! It is not as great as some think it is. In the open road, you really don't need it. When traffic approaches, you have to turn it off because it can slow you down too much, and just weave in and out tracffic to move beyond anyway. Even now that I am used to it, I still find it annoying and turn the distance control off.

[PanEuropean]

Hi Chris - thank's for answering that very old question of mine - I think this was one of the first posts I ever made on Vortex!

You are 100% correct, it is simply not possible (practical) to retrofit this system. In addition to all the components you listed, the complete instrument cluster would also have to be replaced, as there is a small arc of red indicators around the speedometer which serve as a fall-back method of system status notification should the display screen (Y24) fail.

Michael

[PhaetonChix]

I read in Automotive News earlier today that adaptive cruise will be optional on the 2006 NA PASSAT. I wonder if it will be a late availability option on the 2006 PHAETON.

[PanEuropean]

To be honest, I think it would not be very practical in North America, where there is no "lane discipline" on the expressways. It works well in the German speaking countries of Europe, where people get out of the way.

Also, in Europe, if you are doing 150 MPH and you pull up within 1 or 2 car lengths of someone who is only doing 130 MPH, that is taken as a polite notification that you want to pass, and the slower car gets out of the way. If you are in North America, doing 70 MPH and you pull up within 2 car lengths of someone doing 55 MPH in the left lane, that is considered to be a challenge to the slower driver, and the slower driver will usually hit their brake pedal, just to show you who is in charge.

If I lived in Europe, I would buy it. But in North America - as David Z. pointed out earlier, it's pointless.

Michael

[dcowan699]

Here! Here!
I hardly use the regular cruise control simply because traffic is so bad in my area that the minute I activate it, I have to cut it right back off with my brake pedal due to some moron lagging around in the left lane with a handicap emblem on the license plate who BTW probably also dented a Phaeton in a parking lot 30 minutes ago opening up their friggin left door on a slightly slanted supermarket parking lot
Their are times I just about want to pass them using the emergency lane!!

[PhaetonChix]

Quote, originally posted by dcowan699 »

There are times I just about want to pass them using the emergency lane!!

Only in Boston my friend!

~PC

[vwguild]

Actually...I pointed this out in October of 2004....

[dcowan699]

Quote, originally posted by vwguild »

I know. it has always been there...It is just not something that I would ever use...I don't even mess with Cruise Control...Never know what to do with my right foot, and I like being in total control and having that feeling of attachment with the car...

You most certainly did. I feel that way about a motorcycle too. I have cruise control but really only use it on a wide open stretch when my wrist starts to give out.

[PanEuropean]

Quote, originally posted by dcowan699 »

I feel that way about a motorcycle too. I have cruise control but really only use it on a wide open stretch when my wrist starts to give out.

Gee - I have 'cruise control' on my motorcycle too - it's called a throttle lock. When I am in Germany, I just crank the throttle wide open, and engage the lock. Works great, holds about Mach .28 if there are no winds...

Michael

[dcowan699]

All this talk about high speed driving in Germany makes me wonder, how congested is the traffic in Germany? Is the concentration and congestion of cars less there than in America where it's bumper to bumper. Or is it just certain designated highways that allow for such high speeds? Or maybe is it that they are just more liberal about the speed laws in other countries? I've always wondered about that.

[PanEuropean]

Quote, originally posted by dcowan699 »

...how congested is the traffic in Germany? ...is it just certain designated highways that allow for such high speeds? ...is it that they are just more liberal about the speed laws in other countries?

Good questions.

Traffic congestion in Germany does not seem to be a problem to me, although I don't spend enough time in the country to really be able to make an educated observation. What I have noticed is that things are either "really good" or "really bad". Meaning, there are no congestions, and everything runs smoothly, or there is a single, very bad tailback that is a 5 or 10 mile long stop-and-go problem, with smooth flowing traffic on either side.

Only certain stretches of autobahn that meet very strict design criteria for lane width, road surface smoothness, and sight lines allow unrestricted speeds. The surface of the road has to be as smooth as a pool table, for the entire length of the road. Otherwise, the speed limit will usually be 130 km/h (80 KPH).

Also, on the finest stretches of autobahn, although no speed limit is posted, the driver is obliged to choose a reasonable speed, appropriate to the weather, number of other cars present, and so forth. This means that it may be fully reasonable and legal to travel at 300 km/h (185 MPH) on a sunny Sunday afternoon, you would be put in jail for doing the same speed on the same stretch of road (still with no posted limit) on a foggy evening.

In Germany, the laws are much, much stricter about speeding. For example, if you are caught exceeding the speed limit by more than 30 km/h (20 MPH), you not only pay a fine, you lose your driver licence for 30 days, right then and there. So you have a month to spend, as either a pedestrian or a bicycle rider, to think about your past stupidity.

Worth noting that most highways in Germany have 'dynamic' speed limits. There are overhead signs above all the lanes, and in times of bad weather, congestion, accidents, etc., the speed limits will change accordingly. So, the limit may be 80 MPH at 7:30 in the morning, due to congestion, 45 MPH thirty minutes later, due to an accident that closes a lane up ahead (or very, very bad congestion), and then unlimited (whatever you want - 180 MPH is fine) by 9:00 the same morning, after the rush hour is over. Not only are there sensors embedded in the roads to detect vehicle movement, but some of the more advanced cars - such as Phaetons - have automatic two-way data communication with the traffic control system. The car is polled for data every time it passes under a bridge or overhead sign gantry, the car uploads its current speed, etc., and the traffic system downloads safety information about what lies ahead (based on the active destination in the navigation system), such as accidents, constructions sites, speed limit reductions. If you wish, you can set the nav system to automatically re-route you via the 'fastest way', or, have the Phaeton nav system alert you (via the display between the speedometer and tachometer) to problems that lie ahead of you on your route, such as an accident.

Michael

[dcowan699]

Thanks Michael. That's so different actually than I ever imagined. Maybe next year I can go to the GTG there and experience it firsthand.

[PanEuropean]

Here is a link to an excellent website (created by an American) which describes the autobahn system. It is a great 'orientation lesson' for someone who will be driving in Germany for the first time: Driving the Autobahn. There are some minor errors in it, but in general, it is the best introduction and overview document I have seen.

Michael

[PanEuropean]

Here are some photos of the controller and radar transmitter that is use in the Phaeton Active Cruise Control system. This part is manufactured by a company called AutoCruise. Their website is interesting, and worth a visit, but the animation you see in the intro screen shows the transmitter on the wrong side of the Phaeton. The transmitter is on the right front side of the car - behind the same panel on the left front side of the car you will find the Freon connections for the air conditioning system. I do not know if these positions are reversed on right hand drive (UK spec) cars.

Michael

Active Cruise Control System Controller and Radar Transmitter
The small mirror to the upper right of the lens is used to align the transmitter. It needs to be carefully aligned, using the same special tool that is used for Phaeton wheel alignment.

same part, with cover removed

[red5sp1.8T]

Here's a link to a related story about this system in the upcoming Passat:

http://www.autoweek.com/news.cms?newsId=102442

[Realist42]

Impressions – ADC (ACC)

As this is a rare option on the Phaeton, I thought I should share my experiences with ADC on our car.

Firstly, I must confess that I a little bemused about the naming of the system, it is called Automatic Distance Control (ADC) when ordered and Automatic Cruise Control (ACC) in the car, for the sake of simplicity I will just called it ADC.

So, what about ADC, well I have to admit, from the first moment I tried it on a BMW 7, I knew I wanted it, it just makes the driving so much easier, and you drive differently, and I get far less tired when driving on the motorway.

The system in the Phaeton is a send generation system (ish), it is capable of retarding the car if required and can manage the car between the speeds 20mph-110 mph ().
The latest system in the Touareg and MB S-class use a higher resolution radar and can therefore take the car to a complete stop, but these have only started appearing in the last year or so. The system in the Phaeton is, in my view, far superior to the system that I tried in the BMW 7 (in 2005), as it modifies both the distance and rate of acceleration/deceleration, which I like, in the 7 the rate of acceleration was always the same, only the distance changed. For a clam ride on a quiet motorway, it is nicer if the car also accelerates less abruptly. This is also true when compared to the system in the pervious version of the S-Class Mercedes, which was often criticised for being slow in acceleration when pulling out from a car to a clear lane. But that is based on the words of others; I have not tried it myself.

When driving with the ADC, I find that you almost turn into an airline pilot more than driver of a car, you give continuous command to the car about direction, but as for management with in the traffic flow (speed and distance), the car sort all that out for you. You occasionally make a management decision to either increase or reduce the distance to the car in front or to change a lane, but that is about it. I find my self being much more aware about the cars position among other cars as I can worry less about the car in front suddenly reducing speed rapidly. You can also afford to look just a second longer at the SatNav as you know that the car is looking at the car in front for you.

I find that we also use it on normal roads (away from the motorway), but here it does not reduce the load as much and I guess that it is a more UK specific reasons for using it as it really helps in preventing me from speeding, it just manages the speed for me. As you approach a junction or roundabout where there are cars in front, it initiates the breaking procedure and I then complete it.

The biggest safety benefit I find is that it really teaches me to keep a good distance to the cars in front, in the UK traffic is much closer than say in the US or Canada, so we just drive closer to the car ahead. As the ADC system, in the Phaeton, sets the distance to the car in front based on time (the combination of speed and and distance), it ensure that the same amount of time is afforded the driver to react regardless of the speed set. Now, this freaked me out at first, as I would find that on the motorway I would sometimes keep the distance to the car ahead that equated to setting ‘1’ on the ADC at about 70mph, try setting to ‘1’ and then drive 30mph – that just feels way too close! So, I am slowly learning to keep better distance on UK motorways. If everyone had ADC, UK roads would have fewer accidents!

What are the drawbacks and problems of ADC, well there are a couple:

It uses an algorithm to make sure that it ignores parked cars and road furniture. This means that if you approach a stationary car at the back of a traffic jam or a junction, the ADC system just does not see it. This worries me less for junctions, more for motorways. However, as long as the cars ahead of you are rolling, ADC has no problem with spotting them. It even manages to see motorcycles and cyclists, which is very good, but only if they are ‘in front’ of the car.
If you are approaching a traffic jam, if the cars at the back of the queue are rolling at about 5-10mph, with you still doing 70mph+, the system will see this as an emergency, and will initiate breaking as hard as it sees fit and sound an alarm for you to take over – and this works really well, and it is a nice safety feature as I have found it spotted that the cars were really slow before I would have. So, what could have been a close call, turned into a ‘a bit harder breaking than normal’ situation.

As the manual states, the ADC system is not capable of seeing around corners to any significant degree, to ensure that the car does not run amok when you hit resume, it checks steering wheel position and if you are turning, will only accelerate very slowly until it know you are driving in an almost straight line for long enough so that it can get a view of what is ahead. I think VW has solved the problem in a really clever way, and, once you are used to it, it is easy to live with.

One more thing you notice with ADC is that it is a higher order system, i.e. it in turn relies on several complex systems to function, so to turn it on, it checks with all the other systems and needs them all to be ok before activating, it also polls the subsystems during operation to ensure that it can use the breaks when it needs them.
I so far had two occasions where the ADC fell out. First time was in the rain, the system was suddenly seeing stray radar echoes (my deduction) and turned off with a ‘Sensor Dirty’ error, this error is designed to activate with you get snow and ice build up on the front of the car in the winter, as this will obscure the sensors. The car still lets you use the ‘Cruise Control’ as if ADC was not installed on the car. Once the rain had eased, and road cleared a bit, the system happily reengaged.
The other time I suspect that there was a stray error of timeout from one of the subsystems, as the ADC system just failed as I was driving along on the motorway, on this occasion the entire ‘Cruise Control’ system when offline. I stopped a few minutes later, ‘rebooted’ the car and all was fine again, the ADC system started happily.

That is about it, if I were to buy another car, I will be looking for ADC for that car as well, I simply love it!

Best regards,
Johan


Modified by Realist42 at 6:54 AM 12-22-2006

[chrisj428]

I was very fortunate (Thank you, Sandra) to have a W12 SWB with ADC while travelling from Dresden to Wolfsburg, Munich, Luzern and Zurich this past May. It was a great experience!

I had a complete understanding of how the system functions when I set it to 180 km/h with a distance of 2 as I set out from Dresden to Wolfsburg with the Passmores in the car. Nevertheless, as the Phaeton approached it's first vehicle from the rear, there was a momentary "ping" of concern. Fortunately, my blind faith in technology prevented me from hitting the brake pedal and, instead, I allowed the system to function -- something it did brilliantly!

The only negative thing I found after spending a few days with the ADC on the Autobahn and other secondary roads is that it's not available in the NAR and not retrofittable.

[Itzmann]

Wow, what a great description, greatly appreciated.

I'd love to have such a system, though I must confess that the car's inability to "see" much less stop due to a stationary object being across the car's path is a bit worrysome (not that it would keep me from buying it!)

Although you mentioned that you feel more aware of your surrounding traffic with ADC, I wonder if there could be situations where one might sort of "set and forget" and have the chance to become absorbed in hands-free conversation or audiobooks or what have you, and come into stopped traffic at high speed... and I wonder if this is what made the legal worrywarts keep this technology away from us on this side of the Atlantic.

Sounds like third generation vehicles able to stop on their own should be lawyer-safe, though!

[murphybaileysam]

Interesting info but I've noticed that whenever I am on an expressway in the Chicago area, and try to maintain a proper distance form the car in front of me (one car length for every 10 MPH), there is always someone who insists on cutting in front of me and effectively reducing my distance to the car in front. How does the ADC react to those situations?