Coding to modify auto-start stop 'triggers' query

[Odin]

Under normal conditions, as far as I can tell, there's three 'triggers' to the auto start-stop system starting while at a standstill: foot off the brake pedal, steering wheel turned, or vehicle in front moves off (presume that is sensed by the ACC radar). Not considering other factors such as battery voltage, air conditioning etc at this point.

A really annoying habit that 50% of local drivers have while sitting at red traffic lights is that they'll creep forward a tiny bit and stop again, triggering the start-stop system to un-necessarily start the engine.

Is there a way to disable just the ACC radar as a trigger to start the engine after an auto-stop? If so, what's the (OBDeleven) coding path to get to that setting?

[Guest001]

Simple fix is to do the voltage method but its OFF permanently if you do it. I dont know of any way to do what you seem to want and as the radar has nothing to do with it I cant see any way of doing it. Car will turn engine off even if nothing in front of it so dont know where you got that from

Look here for instructions Volkswagen MK7 Golf OBDeleven / VCDS Tweaks List – AutoInstruct

[Odin]

Car will turn engine off even if nothing in front of it so dont know where you got that from

Got it from observations of the behaviour of the vehicle and it's surrounding environment.
Ignoring other factors such as air conditioning being on, or battery voltage drooping below a certain level, there are three other 'inputs' that trigger the auto start-stop to restart the engine once stopped:

1. You lift your foot off the brake pedal
2. You turn the steering wheel
3. The car in front moves more than about 5cm. This would have to be sensed by the chirping radar, surely? (ie not optically via the lane keeping / rain sensing cameras)

I have observed these factors very consistently and with absolute repeatability. Should also mention, this is with a DSG box in a mk7.5 R SE.
I'll take a peek at the link you provided, it may give some clues as to exactly what I need to poke around with to achieve the desired outcome. Thanks!

[Guest001]

Got it from observations of the behaviour of the vehicle and it's surrounding environment.
Ignoring other factors such as air conditioning being on, or battery voltage drooping below a certain level, there are three other 'inputs' that trigger the auto start-stop to restart the engine once stopped:

1. You lift your foot off the brake pedal
2. You turn the steering wheel
3. The car in front moves more than about 5cm. This would have to be sensed by the chirping radar, surely? (ie not optically via the lane keeping / rain sensing cameras)

I have observed these factors very consistently and with absolute repeatability. Should also mention, this is with a DSG box in a mk7.5 R SE.
I'll take a peek at the link you provided, it may give some clues as to exactly what I need to poke around with to achieve the desired outcome. Thanks!

Well i have had a Passat with S/S for 7 years and it didnt make any difference if there was a car in front or not If your foot was on the brake hard enough to stop the engine it would sit all day till you released it. Whether in traffic or not. I just used to lift my foot enough to let it start but still hold the car in place.

If you havent got ACC on the radar wouldnt be operating AFAIK

[ABCD]

As a work around you could try turning off the ACC when you in city driving ie stop start traffic, to see if this disables the "car in front pulling away" trigger? From memory on DAP equipped cars the indicator stalk has a button linking you to the driver assistance menu that you can use to quickly activate/deactivate the ACC.

[DV52]

I dont know of any way to do what you seem to want and as the radar has nothing to do with it I cant see any way of doing it. Car will turn engine off even if nothing in front of it so dont know where you got that from

hmm........... I'm with OP - this from the owner's manual (note last dot point):

Start/stop mode when Adaptive Cruise Control (ACC) is active
The engine will be switched off after the Adaptive Cruise Control (ACC) has brought the vehicle to a standstill with an active braking intervention   .
In the following instances, the engine will restart when the ACC is active:

• If the accelerator is depressed.
• When the ACC has resumed speed and distance control.
• If the vehicle ahead has moved on.

Don

[Guest001]

hmm........... I'm with OP - this from the owner's manual (note last dot point):

Start/stop mode when Adaptive Cruise Control (ACC) is active
The engine will be switched off after the Adaptive Cruise Control (ACC) has brought the vehicle to a standstill with an active braking intervention   .
In the following instances, the engine will restart when the ACC is active:

• If the accelerator is depressed.
• When the ACC has resumed speed and distance control.
• If the vehicle ahead has moved on.

Don

Yes true but what about when ACC is NOT ACTIVE. It still turns the engine off. At least it does in wifes Kamiq and ACC is not turned on in it as no need for it in a shopping trolley. Actually I havent worked out how to turn it on yet as I rarely drive it and wife hasnt a clue about it. I have it permanently disabled in my Tiguan. Kamiq turns engine off if only car on the road and resumes when lifting foot off the brake and just rolls away. Tiguan used to do the same.Passat I had likewise.

[Sharkie]

Actually that is incorrect. I have a DAP equipped R with ACC and it is almost never turned on .... yet, when stopped and the engine off, it will restart the moment the car in front moves .... ACC setting (or or off) has nothing to do with it.

I test (observe) this daily on my commute to work. Even had a whinge this morning abut the idiots in front of me that creep forward at the lights and trigger my engine start

[DV52]

Yes true but what about when ACC is NOT ACTIVE. It still turns the engine off.

@Hillbilly: Of course "it still turns the engine off" if "ACC is NOT ACTIVE". Start Stop is NOT conditional on ACC being ACTIVE (or even being installed) - it's a totally separate facility to ACC, or to the status/existence of the front facing radar.

And in any event, ACC being "NOT ACTIVE" isn't pertinent to the question being asked in this thread - as I understand from OP's words!!

Don

[Odin]

Finally got around to testing this out (wife likes to drive the R too!)
ACC turned off makes no difference to the auto start/stop (restarting) behaviour.
Another reason for the radar not being fully turned off when ACC is turned off is collision detection. If the radar were fully off, how would collision detection still be effective?
I might have to dust off my waveguide diode cavity detector to detect what RF is being emitted from the radar. Presume it uses 24 or 36 GHz?
I should have a bit of time with the R later today to have a poke around the coding parameters and see what might stick out.