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passat170
25-06-2007, 12:16 AM
I bought a new Passat SEL TDI 170 DSG on 1st Sept 06.
From new the car has had a fault with the cruise control.
The button on the end of the cruise control stalk may be depressed to reduce the speed, when cruise control is operative, in 1mph increments. The stalk may also be pulled towards the driver to increase the speed in 1mph increments. The stalk may also be moved up or down to adjust in 5mph increments.
The fault occurs when decreasing the speed by pressing the button on the end of the stalk - if this button is repeatedly pressed (as you need to do if descending on a vehicle in front) the speed reduces by 1mph on some occasions and increases by 1, 2, 3, 4 or even 5mph on some occasions. This is clearly an unacceptable fault!
The VW dealer could not diagnose the cause of the fault.
VW Technical asked the dealer to try another Passat - they did so and told me that the same problem was evident on this other Passat.
So it would appear to be a common fault and I suspect this to be a problem with the ECU software design.
Note that one would not necessarily expect either the on-board diagnostics or the dealer's diagnostic equipment to find a design fault in the ECU software.
The VW dealer spoke to VW Technical and fobbed me off with an excuse that I didn't accept.
VW similarly tried to fob me off and I have not accepted their excuse - I asked for this to be escalated and await their further response.
QUESTIONS:
Does anybody own a Passat with a similar fault on the cruise control?
Can anybody share any further information on this?

Flash2
25-06-2007, 01:50 AM
I never knew you could increase/decrease the speed in 1 MPH increments via the control stalk. When the fault occurs, does it display an increase in speed on the instrument cluster display? (on the multi function display next to the cruise control symbol) I'll try and check this out for you and I'll post my findings.

Regards - Jim.

passat170
25-06-2007, 11:45 AM
Thanks for reply Jim!
Yes when the fault occurs the indicated speed on the digital display increases by 1, 2, 3, 4 or 5mph (and the car does go faster).
If you pause a while before pressing the tap down button again it seems to work fine. But if you press the button repeatedly this is when the fault occurs.
I have never experienced this on any of my 3 previous Golf TDIs or any other car I have driven with cruise control.
I'm eagerly awaiting further news from you!
Jonathan

BenR
25-06-2007, 12:10 PM
This is news to me as well. I thought you could only + or - by about 5 mph by raising or lowering the stalk. I will try this on the way home tonight, rain and traffic permitting!

BenR
26-06-2007, 12:12 PM
Tried it this morning - raising or lowering the stalk gives you a 5 mph increase or decrease in speed. Pushing the button on the end gives you a 1 mph decrease in speed. Useful for fine adjustments.

Flash2
26-06-2007, 07:22 PM
I had a chance to check this out today too. My vehicle seemed to do the same as Jonathan's. I set the cruise to hold 35MPH then I pressed the SET button. The speed decreased in 1MPH steps down to 32 then it jumped back up to 34. Pulling the lever towards me (RESUME) increased the speed in 1MPH steps, but it never jumped to a lower speed. I also connected the car to my diagnostic machine and read the measured values from the switch but the steering control unit seemed to be reading the switch OK.

The vehicle I used didn't have the owner's manual in it, so I couldn't check to see if this is an actual feature of the system. Have any of you two checked the book to see if it says anything about this?

Regards - Jim

passat170
27-06-2007, 01:13 AM
Yes Jim,
The manual says the following:
"Briefly press button SET to decrease the desired speed by approx 1 km/h. Press button SET repeatedly to reduce the speed by several km/h."
So the functionality is not working as intended.
The dealer I took mine too tried another 170 TDI at VW Technical's request and they told me the same fault was evident so I believe it's a common fault on the 170 TDI's.
Can you report your similar fault to VW (I guess your Passat is on warranty)? It will help - if others report the fault they are more likely to correct the error in the software.
There's probably little point in the dealer investigating yours further as the on-board diagnostics and dealer's diagnostic equipment will not find problems arising from an ECU software design error (which I suspect to be the case).
Cheers,
Jonathan

(the SET button being the button on the end of the stalk)

passat170
27-06-2007, 01:16 AM
Ben,
Please try repeatedly pressing the button on the end of the stalk and see if occasionally the speed increases (when it should only decrease).
Thanks,
Jonathan

BenR
27-06-2007, 09:19 AM
Okay. Back soon.

carl s
27-06-2007, 02:29 PM
I've only ever managed to get the speed to increase or decrease in 5mph increments. I'll have to try using the set button, although not sure how it knows to decrease or increase by 1mph I take it's just arbitrarily decreasing then ?

iaint
27-06-2007, 02:49 PM
I've only ever managed to get the speed to increase or decrease in 5mph increments. I'll have to try using the set button, although not sure how it knows to decrease or increase by 1mph I take it's just arbitrarily decreasing then ?


The set button will only decrease by 1mph increments. To increase by 1mph increments you need to pull on the cruise control stalk (the same way as you would if resuming after having cancelled it).

Up and down will increse/decrease by 5 mph increments.

I hope this clears up any confusion.
Iain

Flash2
28-06-2007, 01:10 AM
The dealer I took mine too tried another 170 TDI at VW Technical's request and they told me the same fault was evident so I believe it's a common fault on the 170 TDI's.

Not just 170s, the one I tried was a 140PS model.


Can you report your similar fault to VW

Yes, I'll report it to VW tomorrow.


Jim.

passat170
28-06-2007, 01:44 AM
Hi carl s,
Using the SET button does not command an arbitrary speed reduction, the manual states 1 km/h reduction, but the digital display for the cruise on UK cars indicates in mph and normal operation shows decreases in 1mph increments when SET is pressed with random (faulty) increases of 1, 2, 3, 4 or 5 mph.
Please try it and let me know!
Cheers,
Jonathan

Hi iaint,
No confusion, pressing the SET buton repeatedly decreases speed by 1mph increments with random (faulty) increases of 1, 2 or 3 mph.
Pulling the stalk consistently increases the speed by 1mph (no fault here).
Please try this and see what happens!
Thanks,
Jonathan

Hi Jim,
Thanks for this.
I'm sure that a simple software fix is all that is required.
I guess you own a VW?
But you say the one you tried was a 140PS model so do you work on VWs?
Cheers,
Jonathan

Flash2
28-06-2007, 02:26 AM
Hi Jim,
I guess you own a VW?

Eh...No.


But you say the one you tried was a 140PS model so do you work on VWs?

Yes...Unfortunately.

Jim.

iaint
28-06-2007, 08:21 AM
Hi iaint,
No confusion, pressing the SET buton repeatedly decreases speed by 1mph increments with random (faulty) increases of 1, 2 or 3 mph.
Pulling the stalk consistently increases the speed by 1mph (no fault here).
Please try this and see what happens!
Thanks,
Jonathan




Jonathan

I've tried this several times on my 140 and can not recreate your fault.

Cheers
Iain

BenR
28-06-2007, 08:32 AM
Tried it this morning and I get the same result:

Raise or lower stalk: increases or decreases speed by 5 mph.

Press end: decreases by 1 mph.

Pull stalk back: increases by 1 mph.

It works consistently no matter how rapidly you press.

Flash2
28-06-2007, 09:13 PM
Jonathan, Iain and Ben, could you check and see what model year your cars are. You can tell by looking at the VIN. it will read WVWZZZ3CZ then a number and a letter. Could you let me know what the number and letter are. The vehicle I checked that had the fault was a 6P indicating it's a 2006 model year assembled in Mosel, Germany. Different assembly plants get supplied with parts from different manufacturers. Just wondering if there is anything common between the two vehicles we have here that have the fault and the two without.

Jim

iaint
29-06-2007, 08:33 AM
Jonathan, Iain and Ben, could you check and see what model year your cars are. You can tell by looking at the VIN. it will read WVWZZZ3CZ then a number and a letter. Could you let me know what the number and letter are. Jim

Mines 6E which I assume is an 06. What does the E stand for then?

Cheers
Iain

carl s
29-06-2007, 09:32 AM
I tried recreating this problem and couldn't on mine. The end stalk button decreases by 1mph no matte rhow many times or how quick you push it. pulling towards you increases by 1mph.

Mind you the cruise control on mine was added by the dealer when I bought it so that probably messes up your theory a bit !

BenR
29-06-2007, 10:33 AM
Mine is 7E.

Flash2
29-06-2007, 10:44 PM
Well the two vehicles made in the Emden, Germany (the 'E' in the VIN) assembly plant don't seem to have the fault.

Carl, when cruise control is fitted by the dealer, it is only a switch that is fitted. The cruise control electronics are in the steering electronics ECU and the engine ECU, so it shouldn't mess with my theory. What is the number and letter in your VIN?

Jim.

passat170
30-06-2007, 01:45 AM
Mine is 7E.

Flash2
30-06-2007, 04:18 AM
Mine is 7E.

Ah...well that does kinda mess up that theory, doesn't it.

Jim.

trousers
30-06-2007, 09:17 AM
Never knew there was cruise controle. Where is it and how douse it work please. BOught mine S/H recently with no books. 2003 1.9 TDI

Quatrelle
30-06-2007, 11:50 AM
Never knew there was cruise controle. Where is it and how douse it work please. BOught mine S/H recently with no books. 2003 1.9 TDI
You need to post this in the B5 forum:

http://www.vwaudiforum.co.uk/forum//forumdisplay.php?f=113

You might be able to get a driver's manual from ebay....

passat170
04-07-2007, 12:30 PM
Jim - any update?

VW UK contacted me today, it seems the dealer told them there wasn't any problem with my car. So I told VW UK that the dealer's service manager drove the car and saw the problem when I was in the car with him! So VW UK are going to speak to the dealer again.

I will post further updates as they occur.

Jonathan

trousers
04-07-2007, 09:32 PM
Does anyone have a supplier for whatever is need to fit cruise controle to my 1.9 tdi passat plus a bullet point how to fit it

Flash2
04-07-2007, 09:45 PM
Does anyone have a supplier for whatever is need to fit cruise controle to my 1.9 tdi passat plus a bullet point how to fit it

You can buy the cruise control kit from your VW dealer. The kit comes with installation instructions, but you'll need to find someone with VAGCOM to activate it after the kit has been fitted.

Regards - Jim.

passat170
04-07-2007, 10:03 PM
Does anyone have a supplier for whatever is need to fit cruise controle to my 1.9 tdi passat plus a bullet point how to fit it

Have a look here trousers!

http://www.vwcruise.com/index.html

Flash2
05-07-2007, 07:27 PM
Jim - any update?

Not really. I had another Passat with CCS today. It was a 2006 (E) model with a 1.9 105PS engine. This car also had the fault, but I found that if I pressed the SET button rapid it worked OK. If I did it with a slight pause between presses, the fault appeared. I couldn't get any fault to appear while increasing the speed with the RESUME function. (could you try that Jonathan and see what happens)
I plugged the car into the computer and checked for any software updates for the engine ECM but there wasn't any.
I'm trying to find a vehicle that doesn't have the fault so I can compare the control unit part numbers and software versions to see what the differences are, if any.

Jim.

passat170
06-07-2007, 12:20 AM
I couldn't get any fault to appear while increasing the speed with the RESUME function. (could you try that Jonathan and see what happens)

All other aspects of the cruise control work ok it's just when repeatedly pressing SET when the fault occurs.
J

Flash2
06-07-2007, 08:27 PM
I meant could you try pressing the set button rapidly to see if the speed decreases OK. I found that that worked but if I left a half second pause between presses it showed the fault.

Jim.

passat170
07-07-2007, 02:22 AM
If the SET button is pressed repeatedly (ie quite quickly in between presses) the fault occurs (sometimes the speed reduces, as it should do, in 1mph increments, sometimes it increases by 1, 2, 3, 4 or even 5mph).
The manual states "Press button SET repeatedly to reduce the speed by several km/h".
If the SET button is pressed with a pause between presses it works ok, consistently reducing the speed by 1mph increments.
Thanks for your persistence,
I will let you know when VW UK responds.
Jonathan

passat170
12-07-2007, 12:41 AM
Just had second and final response from VW UK.
VW UK, after speaking to the dealer's Service Manager yet again, advises that there is no fault with the car and that the cruise control is working as intended.
This is the dealer whose Service Manager has driven the car and experienced the fault himself!
VW UK asked if this response ("working as intended") was acceptable and I said NO!
Nevertheless they advised that they could do no more.
So the car is going in to the supplying dealer on Friday 13th July (it was originally sent to another dealer to fix this fault, a noisy wastegate valve and discoloured/corroded wheel centre caps).
The manual states "Briefly press button SET to decrease the speed by approx 1 km/h. Press button SET repeatedly to reduce the speed by several km/h."
Therefore pressing button SET repeatedly should not randomly increase the speed by 1, 2, 3, 4 or 5mph!
It's interesting that the supplying dealer told me that I would be charged if they found no fault under the warranty!
So, after their drive of the car on Friday, there can only be two outcomes:
1. They claim no fault found under the warranty and try to charge me for their time (and I will not be paying as the cruise control isn't working as detailed in the manual) or
2. They acknowledge the problem and try to fix it.
I'm hoping that they acknowledge the problem and try to fix it - a fix is all that I want!
If they can't fix it the Sale of Goods Act gives me further options.
And I am now exploring further options in any event (to be reported at a later date) given that the dealer has reported this as a problem in another Passat they tested and given that this is a safety issue (pressing the button to reduce speed, particularly when approaching vehicles in front, should not cause uncommanded increases in speed!).
Watch this space!
J

Note that after only a few months from new my Passat had a noisy wastegate valve. When I had this repaired under warranty another guy was collecting his car from the dealer and was charged around £145 for the same repair (his car being out of warranty). Another disappointed lady on the phone was quoted £250 to replace a faulty throttle position sensor. It's amazing what you hear when you are sitting waiting to collect your car!
And the wheel centre caps after only a few months had discoloured / corroded - every Golf I have owned had this problem and they haven't corrected it!
The design of these cars is superb,
the build quality is superb,
the ride quality is superb,
the performance is superb,
the reliability is not good and needs to be improved,
sales in Holland is absolutely superb (I bought 3 Golf's direct from a VW dealer in Holland),
sales in UK is disgraceful (this Passat is the only car I have ever bought new in the UK),
service in the UK is disgraceful (I have many stories of poor service, dishonest service, damage to my cars etc)

passat170
17-07-2007, 12:18 PM
Car was taken to supplying dealer last Friday.
They didn't drive it and they suggested the manual could be in error.
This is interesting, after I bought the car the spec reduced and the sales people (including VW UK) advised that the original spec was in error!
After persistent complaining I got a £200 refund on the car because of the reduced spec.
However, I've heard this one before!
So, the car was booked in for the dealer to plug it in to their diagnostics and this is what they are doing today.
The manual is correct and I'm guessing that the dealer won't be able to diagnose the fault because it's likely to be a software problem.
Possibly a problem writing to and reading from memory, possibly an error in the algorithm, possibly a memory overflow error if the SET button is repeatedly pressed and insufficient memory has been allocated for the buffer.
More to follow......

passat170
17-07-2007, 05:41 PM
Supplying dealer has driven the car and acknowledges the fault.
However, as I thought, diagnostics again show no fault on the car.
A DIS report and a copy of the page in the manual have been sent to VW Germany Technical and their response is awaited (will be posted when provided).

Quatrelle
17-07-2007, 08:38 PM
For what it's worth, just checked my French manual and it translates to the same as the English one (Appuyez rapidement et à plusieurs reprises.....). Perhaps VW's translator needs a recall!

passat170
17-07-2007, 11:04 PM
For what it's worth, just checked my French manual and it translates to the same as the English one (Appuyez rapidement et à plusieurs reprises.....). Perhaps VW's translator needs a recall!
Quatrelle - does your cruise show this fault if SET is pressed repeatedly?

Quatrelle
17-07-2007, 11:12 PM
Aaah! - don't use it that often, because I tend to stay off autoroutes. However, next time I'm out in it I'll see what happens, but it won't be for a day or two, unfortunately.

Quatrelle
19-07-2007, 01:34 PM
Tried the cruise control today, pressing the SET button rapidly and brought the speed down, for example, from 90 to 80 kph in 1 kph steps. The only time it sent the speed up was on one occasion when I left a slightly longer gap before the final press, 70 down to 60, when the speed indicated went up to 64 kph, but I couldn't reproduce this, so it might have been me! I'll give it a go next time, but otherwise it was faultless.

Dook
24-07-2007, 01:23 PM
I have had a quick play with this now on my 2007 170ps TDi DSG Estate, and couldn't find anything wrong with it. The only thing I noticed was that when pressing the set button quickly, it was very easy to move the stalk a bit in different directions, which did change the speed the relevant way rather than 1 down, so similar to fat finger syndrome when typing. you sure you keep the stalk absolutely still?

passat170
25-07-2007, 12:12 PM
Hi, thanks for response. Yes I have considered this but the stalk requires a positive pull towards the driver to increase by 1mph and a positive up or down movement to increase/decrease by 5mph. So, pressing the SET button repeatedly to reduce in 1mph increments is definitely not causing inadvertent switching any other way.
Still waiting for response from VW.
Cheers, J

Black
07-08-2007, 11:14 PM
When I ordered my 2008 MY I think I saw in the dealers notes on changes for 2008 that the cruise control stalk design is changing.

This US site seems to support this. Suggests a move to a new design.

http://www.passatworld.com/forums/showthread.php?t=238286

May be worth following up with the ******* it is available on their intranet.

Flash2
08-08-2007, 06:25 PM
2008 models are already being delivered. I've not come across one with cruise yet though. I don't think a change in the switch will cure the problem as it seems more likely it will be a software problem.
I had a 2008 Passat estate come through our workshop today. The tailgate lifts and closes itself. When you lift the outside handle the tailgate lifts and there is a switch on the bottom lip of the tailgate that is used to close it again.
Pretty cool...until it breaks down:(

Jim.

Black
08-08-2007, 06:33 PM
I thought the tailgate closing was an option already available on Passat Estates certainly not something that has been added as standard?
I take it your workshop is not attached to a VW garage.

Flash2
08-08-2007, 06:44 PM
Hey Black. You may be right, but I've never seen that before. I guess not many folk take up the option.

Jim.

passat170
09-08-2007, 01:57 AM
Thanks for the info Black!
I've had a look at your link to passatworld.com and it states "Replace 3-stalk cruise control to new 2-stalk solution".
But I can't find any more info on the web about this.
Do you know what a 3-stalk cruise control is?
My Passat has 3 stalks but only one of them is for cruise control.
If they did update this cruise control stalk, if this cures my problem and if it is retro-fittable then they can easily fit one to my Passat. Until we have more info we are only guessing but keeping an open mind on this it is possible that a new cruise control stalk is intended to fix a problem (why otherwise would they change something that was functioning satisfactorily except perhaps to improve the ergonomics or maybe reduce production costs).
Anyway, here's an update on my situation.....
My car was seen by the supplying dealer just over 3 weeks ago, they couldn't diagnose the fault and they sent a DIS report to VW Germany technical support.
I've not had a response yet so I have written to the supplying dealer to progress.
I'm not talking to VW UK any more after their denial of any problem and after being advised by Trading Standards that the manufacturer has no warranty obligations to me whatsoever (it is the supplying dealer who has obligations to the consumer). So anyone who believes they have an "all-encompassing" manufacturers warranty needs to know that it is worth absoultely nothing! The denial by VW UK of any problem with the car has confirmed this to me. The consumer must refer the matter to the supplying dealer (under the Sale of Goods Act).
I work in QA to exacting standards in the aircraft industry and there's no way on earth I'm accepting a VW dealer or rep telling me there's no fault with my car!
As always I will post further updates!
Do you have any further info on the 2008 updates? Are there body styling updates?
Cheers,
J

Black
09-08-2007, 08:43 PM
I think there are only a few changes.
Dashboard trim change.
Cruise control design
Change in centre armrest stitching!

and that's all I can remember. The dealers have pretty detailed files available on the VAG intranet so if you go into another *********** they may be able to enlighten.

If you look in the new German brochure it is a bit mixed message as it shows a slightly different design of stalk on the SE equivalent but perhaps cruise isn't standard?

https://www.volkswagen.de/vwcms_publish/etc/medialib/vwcms/virtualmaster/de/dialog/media/brochure_pdf.Par.0153.File.pdf

passat170
10-08-2007, 01:05 AM
I will be going into another dealer very soon to ask about the 2008MY changes, will keep you posted!
Many thanks,
J

passat170
14-08-2007, 09:52 PM
Contacted a VW dealer but their information on the 2008MY has nothing on a new cruise control design.
However, the supplying dealer has got back to me after VW Germany advised them that there is a new cruise control stalk (with a new part number) - they have this on order and will fit to my Passat.
Let's wait and see!

shudman
03-09-2007, 12:35 AM
I have a SEL 170 on a 56 plate (check VIN in the morning if need be) and I cannot repro the issue at all.

Stalk up : +5mph
Stalk down : -5mph
Pull stalk : +1mph
Press button : -1mph

Repeatedly pressing the button reduces by 1mph every time I press, even if I do 3-4 a second (if I get repetitive strain injury, I'll know who to blame....)

Hole-In-One
05-09-2007, 09:20 PM
Hi, thanks for response. Yes I have considered this but the stalk requires a positive pull towards the driver to increase by 1mph and a positive up or down movement to increase/decrease by 5mph. So, pressing the SET button repeatedly to reduce in 1mph increments is definitely not causing inadvertent switching any other way.
Still waiting for response from VW.
Cheers, J

Had a test drive of a new 170 sport with Cruise control tonite. Worked perfectly. Very smooth cruise control. single press of the button dropped 1mph, up or down with the stalk went up or down 5mph. The only issue I found (quite logical really) was that if you had banged up the 5mph increment, and then clicked the stalk before it had reached the new speed; it dropped 1mph from the speed the car was doing at the time. i.e. at 55, moving up to 60, if you clicked at and actual of 57.....it then dropped to 56......
Really looked to be a worthwhile add-on to the spec of the car.

Hope this helps......

Rob

shudman
06-09-2007, 12:16 AM
I wouldn't be without cruise control. I have to be honest, after driving in the USA alot, I couldn't figure the use of cruise control on a manual gearbox. How wrong I was. The money is well worth spending.
Atleast in a 30mph zone, you can lock on the CC and concentrate on all those people running out in front of you, instead of watching for speed cameras (and the speedo!)

passat170
06-09-2007, 12:27 PM
New cruise control stalk has not fixed the problem, back to the dealer again!

Slimbarry
06-09-2007, 08:07 PM
For the record, I have a TDI 140 sport with cruise control and it also 'mis behaves.'

While it is on and holding a speed, pressing set repeatedley to reduce the speed in 1mph increments doesn't work. Pressing it twice will drop 1mph and increase it back up 1mph to the original.

I will try other combinations tomorrow.

The 5mph up and down works fine.

Black
08-09-2007, 09:49 PM
Our 1 week old 2008 MY 140 TDI SE has the "traditional" stalk design so I was wrong on the earlier post about the cruise change.
I have tried loads of times to recreate your fault but fortunately with no success! If the stalk change didn't solve it must be an ECU issue....very weird. Are you sure they changed the stalk over? i.e. did you put a subtle mark on the old one!

PS Ours also has the electric tailgate option and that rocks.

wtoram
09-09-2007, 08:35 AM
Hello,

This is my first post to the forum having been a Passat (2.0 TDI 140 SE) owner now for two months.

My car is manufacturing year 2008 (8E in the VIN) and I see the same problem.

As others have observed, when the Cruise Control is engaged and you press the set button repeatedly as fast as you can, there appears to be no problem. However, when you slow the rate at which you press the set button down then first few presses work as expected but then the 'random' increments may appear.

Now, what I have observed is that the 'random' increments are not random at all. In fact they only occur when there is a fairly large difference between the cruise control set speed and the actual speed and they always result in the set speed being set to the current speed. Thus it appears to me that the control unit is making the wrong decision about the intended meaning of the use of the set button.

It appears to me that there is a software design fault since the set button has a dual meaning ('Set' or 'Decrement') and, when engaged, if the speed differential is large enough and the button is not being pressed very quickly, the control unit decides that a 'Set' operation was intended rather than a decrement operation.

It could be that the logic to decide on the intended function of the set button follows steps something like the following:

1: If the CC is not currently engaged, then the operation is 'Set'.
2: If the button pressed is repeated within, say, 0.5 seconds, it is 'Decrement'
3: If the speed differential between the set speed and the actual speed is greater than 2MPH (3kPH?) then the operation is a 'Set'
4: The operation is a 'Decrement'

This would explain why the first few presses are always interpreted as 'decrements'. Assuming the CC is engaged so step 1 does not apply and the button is pressed slowly enough for step 2 not to apply, then what seems to be happening is that as the set button is pressed the first few times, the set speed and actual speed are close enough together such that set 3 does not apply leaving step 4 to decide that the operation is a decrement. But, at some point, the difference between the set speed (which has been decrementing at the rate the button is pressed) and the actual speed (which may be slowing at a lower rate) exceeds the limit and step 3 in the logic applies and thus the button press is misinterpreted as a 'Set' operation.

Obviously, if this is the case, then it is highly likely that no fix - warranty or otherwise - will be available.

I would be interested to hear if others observations agreed with my own.

passat170
18-09-2007, 07:41 PM
Yes Black I can confirm they definitely did fit a new stalk (allegedly a new stalk with a new part number to fix the problem but it didn't fix the problem and, with the part number not being visible, I'm not able to confirm that it was a new part number).

passat170
18-09-2007, 08:02 PM
Yes wtoram, it could be a software problem relating to the moding. Pressing the SET button (when cruise is OFF) turns cruise control into ON mode. In the ON mode pressing SET again should DECREASE_1MPH each time it is pressed. Pressing SET repeatedly when ON should give multiple DECREASE_1MPH commands - the car does slow down and you do see the digital set speed decrease but the fault is apparent by random increases in set speed when you see the digital set speed increase (by 1, 2, 3, 4 or 5mph) and the car does accelerate. The software may be misinterpreting a DECREASE_1MPH command and effecting a SET command.
But also consider this.....
Pulling the stalk towards you also turns cruise control into ON mode. Pulling it again, however slow or fast, consistently commands INCREASE_1MPH. You can be doing 30mph and repeatedly pull the stalk to very high set speeds and the digital set speed always increases in 1mph increments even when the set speed is considerable higher than the actual speed - there are never any occasions when pulling the stalk in ON mode effects a SET command.

passat170
18-09-2007, 08:19 PM
Questions for all respondees:

Please would:

a) All those who have experienced the cruise problem advise if they have DSG or manual gearbox?

b) All those who cannot recreate the cruise problem advise if they have DSG or manual gearbox?

Latest with my car - another DIS report sent to VW Technical Germany this week, response awaited. Car going back to dealer later this week to demonstrate problem (they seem to think it's at low speeds only when the the gearbox wants to drop a gear but I never said this and I'm going to show them that (a) the fault occurs at all speeds with the gearbox set in either DRIVE or TIPTRONIC mode and (b) the fault isn't related to gear changes.

carl s
18-09-2007, 10:30 PM
Don't have the problem, don't have DSG.

Quatrelle
19-09-2007, 03:19 AM
Manual, no problem.

Slimbarry
19-09-2007, 06:10 AM
DSG - yes to the problem of repeatedly pressing to try to decrease by 1mph increments

wtoram
19-09-2007, 05:29 PM
Manual TDi 140 - problem seen.

Romark2001
24-09-2007, 11:36 AM
Went to test mine and the whole system has vanished! Nothing at all comes up in the display when I try to activate the cruise control and the car does not respond to inputs from the stalk!
Guess as I don't use it much the cruise control has packed up and gone on an extended holiday!

akafudge
19-10-2007, 03:06 PM
I have a 2006 140 TDI DSG and I experience the problem. I have just come off the phone with the dealer, as my car has been with them all week, who says there is no fault apparent and VW have no recorded faults logged either.

I think we are between a rock and hard place here. VW and the dealers can't afford to acknowledge the fault and therefore the customer has to put up with it. Or thats how it seems!

Having said that, it's not just VW, it's all car dealers/manufacturers in my experience.

forge197
20-10-2007, 06:43 AM
I picked my Passat SEL up this week and have seen the issue described but I shall not be doing anything about it as it is predictable in its operations.

If you use the SET/-key to drop the speed by multiples then it does jump back especially if you hammer the button. I played with this for a fair bit as I've done a fair few miles already and if you are slow with the - button it's predictable, if you want multiple drops then use the stalk to drop 5mph.

For me I shall not be taking it any further it isn't going to affect my use of the car and I know it's there and how to recreate it so I will use it within the parameters of it working well

compost
20-10-2007, 05:09 PM
I have a 2007 SEL TDi 170 DSG Estate and cruise control peforms as per the manual and no problems to date

Black
20-10-2007, 05:18 PM
Mine does this as well but are you sure it is a fault or that big a safety issue?

The speed jumps "up" on the 4th or 5th push of the button on mine. Someone in an earlier post said it is probably just reverting back to the set function. This makes sense as there is another way of going down 5mph at a time. I can see the designer's logic in that they would think if you needed to trim back speed that much you would use the other method.
As the primary use for that button is to set speed I can see why they want it to revert back.
Perhaps the manual should have a warning in it but it is not really that big a hazard. As they say cruise should only be used on clear roads with little traffic around. Under those circumstances an "acceleration" of 2-3mph is not going to be that unsafe.

forge197
20-10-2007, 05:31 PM
Agree Black with the logic, to me it's a non issue and used cruise today it didn't happen if I need to drop more that 2 mph then I am likely to knock cruise off get to the speed I need and hit set.

claranet
12-11-2007, 11:41 PM
My new Sport 170 is fitted with the optional cruise control. Apart from hiring a Chrysler in the US I have little experiance with cruise.
Firstly, it is very easy when experimenting with cruise control to find yourself having to brake hard as you realise that you are tailgating !! I do not use the cruise control for anything other than motorways and even with motorways as soon as you set the thing then you have to cancel it again ! Maybe I need to get used to it but I'm wondering why I bothered to order it in the first place !

orangezorki
13-11-2007, 12:57 AM
My new Sport 170 is fitted with the optional cruise control. Apart from hiring a Chrysler in the US I have little experiance with cruise.
Firstly, it is very easy when experimenting with cruise control to find yourself having to brake hard as you realise that you are tailgating !! I do not use the cruise control for anything other than motorways and even with motorways as soon as you set the thing then you have to cancel it again ! Maybe I need to get used to it but I'm wondering why I bothered to order it in the first place !

Our problem is that we live in the UK. I hear that some other countries have roads that work. Just a rumour, though, don't quote me!

David.

Quatrelle
13-11-2007, 06:18 PM
Our problem is that we live in the UK. I hear that some other countries have roads that work. Just a rumour, though, don't quote me!

David.I use mine a lot - it's very useful for keeping on the speed limit on our (mainly) empty roads, where it is just too easy to speed, and where, now, there are a lot of mobile radars.....

carl s
14-11-2007, 10:45 AM
Cruise is very useful in all the roadworks we get here where the speed limit is reduced and they put average speed cameras over the whole section.
Definitely worth the £150 option in my opinion.

Black
14-11-2007, 07:33 PM
As a further update to this "issue" I have found that if you hold he stalk down or up it will move in 1mph increments, a short touch of the stalk will do 5mph increments

As discussed earlier I don't think the problem when going down wth the set button is really a problem especially as it seems you can use th stalk for small adjustments.