Is there a way to update or upgrade the ACC in my DSG octavia 2015 so it stops itself in stationary traffic without making me put my foot on the brake and then it re starts itself and resumes the last settings when traffic starts moving?

 

I was told the new superb does this when i had time to kill waiting for my oil service a few weeks back while talking to a chatty salesman. 

Golf from same era also does this. 

 

It's something to do with Octavia not having auto-hold hardware. That feature allows you to be feets off at lights after coming to a stop. 

 

In another words, Octavia only have hill-hold, which can hold the car for a few seconds. This hardware is one level down from auto-hold. This is the reason why one must press brake pedal within a few seconds after coming to a stop. 

2 minutes ago, wyx087 said:

Golf from same era also does this. 

 

It's something to do with Octavia not having auto-hold hardware. That feature allows you to be feets off at lights after coming to a stop. 

 

In another words, Octavia only have hill-hold, which can hold the car for a few seconds. This hardware is one level down from auto-hold. This is the reason why one must press brake pedal within a few seconds after coming to a stop. 

AFAIK this feature needs the EPB instead of a manual handbrake, so the Octavia IV could/should have it.

20 minutes ago, PetrolDave said:

AFAIK this feature needs the EPB instead of a manual handbrake, so the Octavia IV could/should have it.

Yes missed this coming from the Passat, perhaps the MK4 will have it.

3 hours ago, PetrolDave said:

AFAIK this feature needs the EPB instead of a manual handbrake, so the Octavia IV could/should have it.

No I don’t think so. On my MY2016 Superb the EPB doesn’t activate under the circumstances described. The car is held stationary using the autohold mechanism which applies the brakes in the same way that pressing the brake pedal does.

9 minutes ago, nicknorman said:

No I don’t think so. On my MY2016 Superb the EPB doesn’t activate under the circumstances described. The car is held stationary using the autohold mechanism which applies the brakes in the same way that pressing the brake pedal does.

But the Octavia III doesn't have autohold

1 hour ago, PetrolDave said:

But the Octavia III doesn't have autohold

Yes I get that, but I don’t think the addition of EPB will effectively give the car autohold in the circumstances described.

28 minutes ago, nicknorman said:

Yes I get that, but I don’t think the addition of EPB will effectively give the car autohold in the circumstances described.

The Golf 7 and the Superb have EPB and behave as OP asks, the Octavia III doesn't have EPB and doesn't behave as OP asks ..... the two are linked.

 

Without EPB the Octavia III only has a "hold" of a few seconds as the hydraulic pressure is held by the ABS, but the Golf 7 & Superb have autohold which uses the EPB.

 

There have been several threads in this Octavia III forum on what features the Octavia III is lacking because of it having a manual handbrake instead of EPB, worth reading them?

Edited 13 December, 20196 yr by PetrolDave

My question is whats the point of it? To me it is no great shakes to put your foot on the brake pedal and hold it.

On 13/12/2019 at 16:38, PetrolDave said:

The Golf 7 and the Superb have EPB and behave as OP asks, the Octavia III doesn't have EPB and doesn't behave as OP asks ..... the two are linked.

 

Without EPB the Octavia III only has a "hold" of a few seconds as the hydraulic pressure is held by the ABS, but the Golf 7 & Superb have autohold which uses the EPB.

 

There have been several threads in this Octavia III forum on what features the Octavia III is lacking because of it having a manual handbrake instead of EPB, worth reading them?

Well I can only talk categorically about the Superb, but on that car the EPB categorically has no part in autohold. Example: stop at lights, take foot off brake, autohold keeps car stationary indefinitely. Operate EPB manually - one can hear the motors whirring. Red parking brake light comes on. Put DSG into N, which cancels auto-hold. Car moves slightly as front brakes (which were on due to autohold) release. Incidentally the brake pressure for autohold doesn’t come from “ABS holding the pressure”, it comes from the same source as is used by the traction control which can apply brake pressure to one or more wheels without the driver pressing the brake pedal.

 

So whilst I cant say much about the Octavia, I can definitely say that EPB is not used for Superb autohold, nor on my sister’s Karoq. I would be fairly confident that there is no direct connection between no autohold and no EPB on the Octy, it just has a lower equipment level.

On 13/12/2019 at 21:33, Ecomatt said:

My question is whats the point of it? To me it is no great shakes to put your foot on the brake pedal and hold it.

It’s just more relaxing. For my sister, who is severely disabled and has recently moved to hand controls, it is great.

 

Not sure if the Octy comes with ACC but if it does and on a DSG model, does the car completely stop behind stationary traffic in front, indefinitely until the car ahead moves off (after dabbing the throttle if more than a few seconds has elapsed)?

 

If the car has ACC, that means the computer can apply the brakes, which surely means there is no fundamental reason why it could not have auto-hold.

 

Since the Superb already has all the necessary equipment it is just a matter of including appropriate software to enable auto-hold to happen. Plus a button to turn it off if you don’t like it. So the manufacturer can add the feature for virtually no cost.

Edited 15 December, 20196 yr by nicknorman

Just a related ACC question . Do the brake lights come on when ACC slows the car down to the speed of the one in front?

35 minutes ago, vade04 said:

Just a related ACC question . Do the brake lights come on when ACC slows the car down to the speed of the one in front?

 

Yes, if it involves braking (rather than just throttling off).  Does on my Golf anyway.

 

Gaz

ACC is great for traffic jams very relaxing and makes the driver lazy.......until you pull over towards the hard shoulder and it starts to accelerate as the ‘lane’ is clear.... even though the driver side 1/2 of the car is pointing at the left hand rear of the car 15 feet in front. 

2 hours ago, vade04 said:

Just a related ACC question . Do the brake lights come on when ACC slows the car down to the speed of the one in front?

If the brakes are applied then yes the brake lights come on.

1 hour ago, Redboy said:

ACC is great for traffic jams very relaxing and makes the driver lazy.......until you pull over towards the hard shoulder and it starts to accelerate as the ‘lane’ is clear.... even though the driver side 1/2 of the car is pointing at the left hand rear of the car 15 feet in front. 

Like all complex system automation it isn’t perfect. One needs to understand the behaviour of the system and know when a need for manual intervention is likely.

Just like in aviation where manual flight controls have been largely replaced by automation, the pilot nevertheless ultimately needs to be able to fly manually if systems fail or glitch. Which of course increases training burden, because the pilots have to be trained to fly manually AND to use the automation properly.

 

Same with cars, whilst the automation does reduce driver workload and fatigue, it nevertheless requires the driver not only to be able to drive manually, but also to understand how the systems will behave in various situations and when intervention is likely to be required.
 

A classic example is that whilst the ACC will slow the car to a stop if necessary, when the car in front stops, if you come round a corner and find stationary traffic ahead of you, the car won’t stop in time. You need to brake manually. This of course being because unless the car in front is moving or has recently been moving whilst in view of the radar, it can’t tell the difference between stationary traffic and, say, a house or tree on the outside of a bend - it can only tell the difference by Doppler shift of the radar return from a moving vehicle not matching the speed of the car.

 

If you don’t know and understand that, you will quickly come unstuck! If you do know and understand it, it is not a big deal.

Good explanation re doppler effect. Yes they are there to assist, not take over the driving.  I confess that ACC seemed to be so clever , that it almost caught me out when I pulled over in a traffic jam to allow a police car on blues and twos to filter through. It was for me a cautionary note, which is why I posted about it. On a positive side, the reverse sensors stopped me dead on Saturday when my inattention almost ended up in a parking faux-pas, so full marks to the system's designers.  

17 hours ago, nicknorman said:

Well I can only talk categorically about the Superb, but on that car the EPB categorically has no part in autohold.

 

It might not have a link from a user point of view but some of the 'modules' have bundled capabilities. The modules and sensors fitted to cars with EPB may be needed to allow the function of autohold

 

There are issues like this all over the VAG MQB-generation cars mainly involving cameras and door modules. I am sure if you drill down into the control module revision numbers and coding using VCDS there will be something fundamental missing from the Octavia that the cars with EPB have.

 

15 hours ago, nicknorman said:

whilst the automation does reduce driver workload and fatigue, it nevertheless requires the driver not only to be able to drive manually, but also to understand how the systems will behave in various situations and when intervention is likely to be required.

 

Very true. Best one is the use of indicators, to have the car accelerate hard when you indicate to pass a car in front is something you need to be prepared for.

1 hour ago, flybynite said:

 

It might not have a link from a user point of view but some of the 'modules' have bundled capabilities. The modules and sensors fitted to cars with EPB may be needed to allow the function of autohold

 

There are issues like this all over the VAG MQB-generation cars mainly involving cameras and door modules. I am sure if you drill down into the control module revision numbers and coding using VCDS there will be something fundamental missing from the Octavia that the cars with EPB have.

I know what you mean in principle, but I remain sceptical that the EPB and auto-hold are linked like that. The EPB is not “clever”, although obviously it needs to receive communications from other units so that it is automatically applied when the selector is in P and engine is stopped, also so that it automatically released when throttle is pressed with transmission in D/R (or for a manual, when the clutch is raised in gear).

 

Presuming the Octy has traction control and or autonomous emergency braking etc, it has the physical infrastructure to apply pressure to the brakes without driver intervention and so I can’t see a fundamental reason why it couldn’t do autohold, and I can’t see any reason why any aspect of EPB would be relevant.

 

But I suppose ultimately, we are both guessing!

Edited 16 December, 20196 yr by nicknorman

1 hour ago, nicknorman said:

I suppose ultimately, we are both guessing!

 

I'm not guessing, I have admaps of all the systems on my computer, tracing this sort of thing takes time and effort that I don't have as I know it is not going to be possible to get the Octavia to autohold.

 

I think you are looking at it in quite a simplistic way, and as such I can see why you would think it should be possible.

 

Have you looked at a scans of channel 03 and 53?

 

Did you know that the EPB on a VW has coding links to these sensors and modules

Brake Electronics (J104) Control Module

Steering Angle Sensor (G85)

Lateral Acceleration Sensor (G200)

Brake Pressure Sensor 1 (G201)

Longitudinal Acceleration Sensor (G202)

Longitudinal Acceleration Sensor (G251)

Parking  Brake Electronics (J540) Control Module

 

Have you looked through the coding in all those sensors and modules to see where you would have to unpick the references to the EPB module J540

 

IMHO the Brake Electronics Control Module (J104) would be looking for the input from the Parking Brake Electronics Control Module (J540) before it would work. The Octavia does not have this module so would not provide the input, Fitting it would not help as it has no electronic parking brake, therefore the parking brake module would fault causing the brake module to fault.

 

There are also type approval issues as hydraulic holding of a car is not the same as mechanical holding of a car and is not approved as a replacement.

 

Having to put a screwdriver through the tunnel between the propshaft UJ to pass an MOT in a car with a hydraulic handbrake conversion taught me that.

 

Edited 16 December, 20196 yr by flybynite

On 13/12/2019 at 21:33, Ecomatt said:

My question is whats the point of it? To me it is no great shakes to put your foot on the brake pedal and hold it.

Or, even better, put the handbrake on, don't dazzle the driver behind and properly hold the car in case someone at the back doesn't stop.