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trident
19-11-2007, 10:19 AM
Hi all you clever ones. Any body have any answers to the questions below.

A question about the DSG gearbox.

When in “auto hold” brake mode with the gearlever in “D” and stationary at for e.g. a traffic light, --- what is the status of the gearbox as per the questions below.


I assume it keeps gears 1 & 2 selected
Are the clutches esp. for gear1 completely disengaged or do they remain in the drag/creep mode?
If they (the clutch) disengage completely, after how long at stationary?
Is the same effect as 2 when the hand brake is engaged as opposed to auto hold?
What is VWs recommended procedure when stationary? To disengage and place in “N” or leave in “D”. If left in “D” will this affect the clutch life?
I appreciated that there is a whole series of questions above but thank you in anticipation of a reply.


Regards

Trident

DSGboy
19-11-2007, 03:24 PM
I wonder whether its really recommended to leave the car in autohold for more than a few moments. It would be unfortunate if you were to accidentally touch the accelerator while in queued traffic. I'd be interested to know what other people think.

karro
11-04-2009, 08:25 PM
If you have to return to Neutral each time you stop, what is the down-to-earth advantage of the DSG over a manual box?

DSGboy
11-04-2009, 08:33 PM
you dont have to change gear, and the dsg changes gears faster and makes more efficient use of the engine's power.

what i meant in my post was that sitting with the car held on autohold is like sitting with your finger on the trigger of a gun - the slightest nudge of the accelerator and you'll be heading forwards, possibly into traffic. i dont believe sitting on autohold does any damage to the car - in fact after a minute or two the car itself automatically switches onto the handbrake or something like that

mrmitch
12-04-2009, 03:15 PM
All very good questions that I have been asking myself for a while.

This is only speculation but -

Auto Hold only engages when presumably all 4 road wheels come to a complete standstill. (Otherwise a front end lock-up would activate Auto Hold) - This is what normally happens when you apply the footbrake and brake to a halt (and apply the hand-brake in a normal car:p) - so gear 1 must automatically disengage when at a halt i.e. there is some sort of slipping clutch mechanism. Therefore it cannot be doing any damage to sit still in Auto Hold for virtually any length of time. You can be sure that if there was a problem it would be mentioned 50 times in the manual.

As soon as you apply some throttle, Auto Hold releases and you are off :D. So the clutch device must engage virtually instantaneously - it is cetainly not detectable and there is no perceptible lag.

I havent tried pressing the hand-brake button at 50mph but I suspect it will not work - a safety interlock? Which then prompts the question how do you stop a car with no normal brakes? - normally you use the hand-brake or safety brake as it used to be called. Anyone brave enough to try it and prove me wrong?

Personnaly I think DSG / Auto Hold combo is absolutely excellent. My only two gripes are -
1. The Auto Hold button is set-up for left hand drive and is obscured from the drivers view by the DSG selector - it should be relocated on the right for RHD cars.
2. Auto Hold should be selectable as a default ON condition, so that you switch it OFF by choice, and not every time you put the selector into P or undo the seat belt. I have nearly had more 'accidents' through this that through forgetting Auto Hold is ON. (This is made worse by point 1 as you cannot readily see the AH light has gone out without bending your head around the DSG selector)

Overall though, Im glad I have got DSG/AH and most people have not.:biglaugh:

If there are any proper VW engineers out there that can explain how this all works I would be very interested to hear from them.

'57 SEL TDi 170 Estate DSG Reflex Silver, 29k. The Silver Machine.

ledburyloafer
12-04-2009, 06:50 PM
All very good questions that I have been asking myself for a while.





I havent tried pressing the hand-brake button at 50mph but I suspect it will not work - a safety interlock? Which then prompts the question how do you stop a car with no normal brakes? - normally you use the hand-brake or safety brake as it used to be called. Anyone brave enough to try it and prove me wrong?





'57 SEL TDi 170 Estate DSG Reflex Silver, 29k. The Silver Machine.

Oh yes it will! just keep your finger on the button and wait for your internal organs to be rearranged!:banned:

Quatrelle
12-04-2009, 08:09 PM
I haven't had the courage or need to try it, but it's a legal requirement to have an emergency brake, i.e. a handbrake so, as ledburyloafer says.....

Go on then ledburyloafer, a bit more detail?

mrmitch
12-04-2009, 08:22 PM
Well done Ledburyloafer... did you do it by accident, out of curiosity, or in an emergency??

Well maybe I will try it at about 15-20mph first!;)

Ledburyloafer's reply infurs that the button action changes from toggle on/toggle off to having to hold the button in (i.e. as soon as you release it the brakes come off)?. If that is the case there must be a transition speed when it changes from one action to the other. I wonder what that speed might be?

I assume the handbrake works on the rear wheels, I havent looked underneath. Do you know whether it works directly on the rear discs, on small drums within the discs, or by some other over-complex arrangement?? Its as well to know what to expect when you try it at 50mph.

Quatrelle
12-04-2009, 08:55 PM
It works on the rear discs.

martin1810
12-04-2009, 09:15 PM
Handbrake works by turning an electric motor which winds the pads onto the disc. If the cars not moving the motor stays locked at that point. i.e Handbrake on. If the car is moving the electric motor doesn't stay locked so when you release the button the pads are free again. The motor does not need to wind back to free the pads for this but it does need to wind back when you release the handbrake with the car stationary. The MOT tests the car on rollers and so they have to be able to press the button with the wheels turning so as to read the stopping force. Hope this helps.

Spudrig
13-04-2009, 09:22 AM
I didn't have the guts to try out the 'hold the button' technique :p I was going to try it in a carpark when it was snowing in February, but didnt :D

ledburyloafer
13-04-2009, 10:10 AM
no half measures< everything comes on! bang all four wheels, did this in a carpark, enough to say that you wouldn't try it on an open road!:eek::eek:

mrmitch
13-04-2009, 05:11 PM
All good stuff, especially the technical stuff from martin 1810. So the transition speed is anything above zero mph and you have to hold the button on, at least I know now. I think I will wait for a safe opportunity to try it out though.

ledburyloafer seems to suggest all 4 wheels lock-up I think ? Is this correct, or is it back wheels only? Could make a difference if you are mid-wet-corner.:eek:

No more questions for now, thanks for all your input guys.:beerchug:

'57 TDi 170 SEL Est DSG, Reflex Silver, 29k, "The Silver Machine"
Auto Glym Complete Valet Pack purchased and applied three times - Shiny!. One Valet service £25 - not as good a job but the car was filthy after the snow and it was bloody freezing.
Missing second Boot Hook fitted by Dealer 'free of charge' after about 6 weeks.
Thule Aero Bars, 755 Feet and 2-off cycle carriers delivered, fitted, excellent.
Pure 1500 DAB and Creative Zen media player used through Kensington (?) FM Transmitter - works fine.

Quatrelle
13-04-2009, 06:19 PM
ledburyloafer seems to suggest all 4 wheels lock-up I think ? Is this correct, or is it back wheels only? Could make a difference if you are mid-wet-corner.:eek:
Rear wheels only - see earlier.

Let it roll back gently, and apply - the rear will rise, forward and the rear will sink due to the design of the rear suspension.

The Fingers
14-04-2009, 02:51 PM
Ok the whole hand break thing had me this morning so i thought i would give it a go a lunch time.

:firedevil

All i can say is - 40 MPH on a straight road - kept finger pressed on button - THEN...... HOLY SH*T - i am not doing that again unless i have to.

My eyes have only just gone back in their normal place:bigeyes:, and there is a strange brown stain in me pants

It didnt seem to lock the rear end up but it was definatley braking hard, the back end sat down first then the front seemed to follow suit, i thought it may have been the ESP trying to stablise the car.

If you ever need to use this it is going to stop you - VERY FAST

Its all FUN:biglaugh:

Steve400N
01-12-2014, 06:49 PM
Hi

Random question im intrested in test driving the Golf R with DSG and the new Audi S3 with Trip tronic.

I would like to know when you have the car in manual mode is it trully down to the driver to change gear. As ive always wondered if u dont change down in manual mode the car will do it for u as its a auto box. Please help

RichardSEL
02-12-2014, 08:14 AM
Yes, you cannot fully cheat the downshift -- like stay in fourth when you're in a gearbox pre-programed designed slow second speed. But you can in upshift -- like stay in second to red line and then shift up. This holds true for both DSG and Tip boxes. You can change down to second to get overrun braking -- but feels as if that doesn't give you as much slowing as a manual box would say down a hill, IMO.

Best experienced with paddles. Great fun! But be warned you might become used to this mode and then want to boot your way out of a roundabout or turn. Yet can't coz the paddles are fixed to the steering wheel which has turned the paddles away from where your hands are. Some people, especially overseas HGVs appear not to respect the "give way to traffic from the right" roundabout convention. And I nearly got caught out coz driver didn't expect me to continue out thru the gap he went for. Paddle extenders are available from e-Bait

vespa
02-12-2014, 03:08 PM
My last car was Auto steptronic and a previous car 3 speed Borg Warner. Whilst neither car was anything like the DSG box both driving manuals said engage neutral if stopping for more than a few seconds. I assume that a similar proceedure should be applied to the DSG box. Something in the box will be wearing away if you stay in gear when stationary. I assume that the electronic brains in the car will look after themselves regarding the proceedure you mention to avoid severe damage. Why not contact VW direct to see what they recommend.
DSG : Volkswagen UK (http://www.volkswagen.co.uk/technology/transmissions-and-drivetrains/dsg) & Direct-shift gearbox - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Direct-shift_gearbox)