Hold Assist and Adaptive Cruise Control

[sifreed]

I have recently ordered an A3 Sportback S line with S tronic, ACC, but not Hold Assist. Thinking of adding Hold Assist but wondering if it is needed when using ACC in traffic. I am assuming that the ACC will bring you to a complete stop in traffic and hold you at a stop until the traffic starts again? Can anyone with S tronic and ACC confirm please?

Also, for anyone with ACC and S tronic, how have you found this setup generally in stop start traffic? I have read through this forum, but could not find any posts on this aspect of AAC.

 

[snakehips]

I'm no expert and did not order ACC but there is no way I'd leave it to ACC to pull up to a stop behind another car in stop-start traffic! That would totally freak me out, and I don't think is what ACC is intended for. But I'll let others say if they use it like this.

 

[Sandra]

I have recently ordered an A3 Sportback S line with S tronic, ACC, but not Hold Assist. Thinking of adding Hold Assist but wondering if it is needed when using ACC in traffic. I am assuming that the ACC will bring you to a complete stop in traffic and hold you at a stop until the traffic starts again? Can anyone with S tronic and ACC confirm please?

Also, for anyone with ACC and S tronic, how have you found this setup generally in stop start traffic? I have read through this forum, but could not find any posts on this aspect of AAC.

Hi, welcome to audi-sport.net. What is estimated delivery on your car? What colour did you choose? The guys in here are all very friendly and helpful. Enjoy the forum. x

 

[sifreed]

Thanks Sandra. I went for Shiraz Red. The full spec is:

S line 1.4 TFSI cylinder on demand S tronic
Adaptive Cruise Control
Park Assist
SE suspension
Technology package
10-spoke alloy wheels

Delivery not until March 2014. But that seems par for the course from reading these forums. I am reading lots about the car whilst I wait. But having read this forum from start to finish, I still have 5 months to wait

 

[Sandra]

Time will pass quickly. There is always lots going on in here. x

 

[snakehips]

Cool. Welcome to the very exclusive Shiraz Club!
i suspect only the Beluga Club can claim more exclusivity.

 

[arad85]

You may find this an interesting watch on ACC: Audi A7 - Adaptive Cruise Control in Heavy Traffic - YouTube

I have been told (although I don't know how true it is) that you need to turn off stop-start for HH to work and that it works well around town where stop-start may be a little too slow when you need to pull out quickly (say at a roundabout). Having driven an s-tronic A3 the other day, stop-start only comes on when you depress the brake quite hard - you can have your foot on the brake enough to stop the car, but not hard enough to engage stop-start. I would expect HH to work in the same way - it only comes on when you depress the brake quite hard. Given ACC does all the work, my expectation is that HH is disengaged in this mode, but that's only what I'd expect... not what I know (I've also ordered ACC & HH).

 

[Jeff777LUFC]

Ive not used it to a great extent but so far i have found you can absolutely rely on the ACC in stop start traffic. The above video shows the operation pretty well. I also found it sometimes does not start you moving again when you come to a complete standstill, and you have to give a little touch of throttle to re-activate it.

I haven't got HHA but don't see why it wouldn't work fine in conjunction with stop/start.

 

[cemerson]

I'm no expert and did not order ACC but there is no way I'd leave it to ACC to pull up to a stop behind another car in stop-start traffic! That would totally freak me out, and I don't think is what ACC is intended for. But I'll let others say if they use it like this.

It is intended for that, and designed for exactly this (on the s-tronic).

 

[Tom75]

Hi,

I have ACC and hold assist. In the beginning I have to say I was really skeptic to ACC in start stop traffic since I was used to a normal cruise control from my previous car. However I have used the AC now for a while and have to say this is the best thing I ever had. It works just perfect in slow start stop traffic, its totally reliable and very smooth. For example when I now drive to work in the morning I put on the ACC and don't need to accelerate or touch the brake until I'm there. So this is definitely a must have if you like relaxed driving.

Anyway I have also hold assist and I am actually not sure how the ACC would work without that because if the road is not flat ACC will need a a handbrake to hold the car I I think it would be quite pointless to use ACC in heavy traffic and operate the handbrake manually?

In really slow start stop traffic I am normally switching off the start stop system because then it stops the engine every time you come to a hold after whatever 1m or 30cm rolling.

Regards,
Tom

 

[snakehips]

It is intended for that, and designed for exactly this (on the s-tronic).

I stand corrected! But it would still freak me out too much for me ever to use it in that situation. I don't have THAT much faith in technology.

 

[arad85]

Thanks for clarifying the HH and ACC Tom - turning off the stop-start in the morning crawl is also how I'm envisioning using the system too.

 

[arad85]

For example when I now drive to work in the morning I put on the ACC and don't need to accelerate or touch the brake until I'm there.

One other question...

In the video I posted above, the US driver says he has to blip the accelerator again to get the car moving if he has come to a complete stop. Is that the same ith the UK car or is it a complete set and forget system?

 

[constvoid]

I have ACC without hold assist. I've never driven a car with hold assist but I can't see a benefit for it with the ACC and S-tronic combination.

When ACC brings the car to a halt, you get a few seconds where "Automatic Go" or something similar is displayed on the DIS. During that time, stop-start is not activated and the car will pull away if the traffic ahead moves off. After this time, stop-start is activated, and the car will be held by ACC on the brakes, effectively indefinitely. This is the situation you're seeing in the video - you either touch the throttle or pull the CC lever to restart the engine and pull away. If you pull the lever when in stop-start, and the traffic ahead has not pulled away, you again get a few seconds of "automatic go" and stop-start is deactivated. Note that I wouldn't use th throttle in that situation as this tends to override the ACC and you'd end up in the back of the car ahead.

Finally, If you deactivate ACC while it is holding the car stationary (by pushing the CC lever), the parking brake is automatically applied - this is roughly equivalent to hold assist, but the PB is only applied for you in that specific situation.

Ian

 

[M_D_O_London]

ACC with S-Tronic + Stop Start + HHA works well. Not had long to play around with mine yet but from my initial experiences, it's phenominal just how smooth the ACC system works - especially in traffic. Genuinely need to applaud the R&D team who engineered the tech!

HHA is smooth to apply the brakes when stationary, (so smooth that you don't notice it). When pulling off, it releases immediately. When stop-start has kicked in, just tap the accelerator briefly and the engine will restart whilst the HHA stays active enabling you to make a swift get-away.

Also - re the stop start system in traffic, the engine won't cut out unless you push the accelerator down firmly. It is possible to come to a stop and just have HHA hold the car without the engine cutting out - just don't push the brake down too far.

 

[JohnM100]

I have been told (although I don't know how true it is) that you need to turn off stop-start for HH to work

Not true. Hold Assist & stop/start work fine together.

However separate discussion on Hold Assist and ACC and I can't comment on that.

John.

 

[arad85]

Thanks for the clarification

 

[cemerson]

Not had long to play around with mine yet but from my initial experiences, it's phenominal just how smooth the ACC system works - especially in traffic. Genuinely need to applaud the R&D team who engineered the tech!

Agree - I've got used to it now but it's an awesome system. It's the one thing that almost makes me wish I got the s-tronic version (almost...)

 

[sifreed]

Thanks all for such great replies. What a great forum/community!

I think Ian has the closest setup to what I have ordered (S tronic and ACC without Hold Assist) and confirmed what I suspected - that you effectively get the functionality of Hold Assist for free when using ACC. i.e. if it has brought you to a complete stop it will keep the brakes on automatically for you until the traffic moves again (within 2 seconds) or until you manually resume ACC with the lever or accelerator.

So I think I'll save £90 and not add Hold Assist to my order

 

[snowfree52]

yes but you don't have 100% of the time the ACC on ! I have ACC + Stronic + hold assist and I think the hold assist in worth taking !

It's not really expensive and it works well

 

[cemerson]

Hold Assist is great for the times you aren't using AAC though, and is only £90

 

[cemerson]

I thought the ACC with s-tronic would move off automatically if you were still for less than 2 minutes, not 2 seconds? That's what I remember from the manual anyway

 

[snowfree52]

no, it deactivates after 2-5 seconds
looks boring, but if you think about it, imagine you're at a stop, the guy in front is there for 1 minutes then goes, and your ACC lauches at full speed by himself, must be a bit scary.

 

[cemerson]

Yeh, though the ACC doesn't really ever launch at 'full speed' in my experience I can understand there being a cut-off, just thought it was longer

 

[snowfree52]

never tried for the moment because of running-in but in our A4 B8 3L TDI, if you put the ACC in dynamic it goes at full throttle when it lanches

 

[cemerson]

I put mine in dynamic today (have had it in auto up till now), but still seems quite 'leisurely' in its acceleration, even with nothing in front

 

[snowfree52]

they must have changed it, anyway it was a bit too much, well that's what dynamic is all about I guess