Brake lights with auto-hold

[LeylandVCDS]

Quick question on possible coding of auto-hold - 2019 Leon 2.0TDI DSG facelift with electric handbrake

If the autohold button is selected (rearmost of the 2 handbrake switches), I've noticed that the brake lights stay on as long as the autohold is active and the green handbrake warning light is showing on the dash - for example, stationary at traffic lights - even when the footbrake is not in any way pressed. Personally I find being behind anything with brake lights on like this is both unnecessary and unsociable, especially on a wet night. Anyone know if it is possible to change coding so that the brake lights go off when the brake pedal is released when autohold is active?

Thanks

 

[cairus]

I was not aware that the function could be programmed

 

[Glosphil]

At night, when stopped for more than a few seconds, my solution is to pull the Electronic Handbrake switch which activates the EHB & also deactivates the AH. This extinguishers the brake lights. The EHB automatically releases when the accelerator is pressed & the AH will still be active at the next stop.

 

[Craig.]

You'll need to establish how the brake lights are triggered in this instance as if the brake pedal is not engaged then the brake light switch (if there is one at the pedal) is not triggered and the brake light activation is being signalled from elsewhere (pressure maybe?).

Once that's established then you can pinpoint where the coding or parameters might be for that trigger from AH, if they exist!

I've not checked the diagrams for a brake pedal switch so seeing if that is there would be a good thing to check too

 

[cairus]

Auto Hold works with the last stored brake pressure and this triggers the brake light. Changing this requires a different data set in the ABS block.

 

[DEAN0]

These guys have managed it on a 2018 Audi S3

How do you disable brake light Hill Hold Assist / AutoHold? | OBDeleven

Hi I have a real bugbear with stopping at lights and the car in front dazzling me with their braking lights instead of using their handbrake. I recently upgraded from a '03 Golf Tdi to an '1

forum.obdeleven.com

 

[cairus]

Correct, but then you no longer have a brake light when assistants like ACC etc. intervene

 

[RUM4MO]

Quick question on possible coding of auto-hold - 2019 Leon 2.0TDI DSG facelift with electric handbrake

If the autohold button is selected (rearmost of the 2 handbrake switches), I've noticed that the brake lights stay on as long as the autohold is active and the green handbrake warning light is showing on the dash - for example, stationary at traffic lights - even when the footbrake is not in any way pressed. Personally I find being behind anything with brake lights on like this is both unnecessary and unsociable, especially on a wet night. Anyone know if it is possible to change coding so that the brake lights go off when the brake pedal is released when autohold is active?

Thanks

I respect your wanting to stop this happening, now I'll need to check what happens when the Hill Hold is "on" in my 2011 Audi S4 - I've only had it since July 2013!
If this does not switch the brake lights on in my 2011 Audi S4, what was VW Group thinking about making hill hold switch on the brake lights on any other cars!

 

[cairus]

Be careful, the Hill Start Assist or HHC is different from Auto Hold... HHC is controlled by the ABS's inclination sensor, so it has to recognize that you have a certain incline going uphill and the vehicle is only held against rolling backwards for a certain short time without the brake lights.

 

[Seriously?]

I respect your wanting to stop this happening, now I'll need to check what happens when the Hill Hold is "on" in my 2011 Audi S4 - I've only had it since July 2013!
If this does not switch the brake lights on in my 2011 Audi S4, what was VW Group thinking about making hill hold switch on the brake lights on any other cars!

Not just VW group...my Mercedes 204 C Class did the same thing when the "Hold" function was enabled.

 

[LeylandVCDS]

I respect your wanting to stop this happening, now I'll need to check what happens when the Hill Hold is "on" in my 2011 Audi S4 - I've only had it since July 2013!
If this does not switch the brake lights on in my 2011 Audi S4, what was VW Group thinking about making hill hold switch on the brake lights on any other cars!

It's not the Hill Hold function I'm questioning - it's the auto hold that operates automatically when the vehicle comes to a stop and which brings on the green handbrake warning light (rearmost switch of the handbrake switches). Totally different from Hill hold

 

[RUM4MO]

Yes but, t

It's not the Hill Hold function I'm questioning - it's the auto hold that operates automatically when the vehicle comes to a stop and which brings on the green handbrake warning light (rearmost switch of the handbrake switches). Totally different from Hill hold

Maybe, but the function that is given the name "hill hold" or "hill hold assist" etc by VW Group, all perform the same function, ie they engage when (in some cases only if manually selected) as soon as the car comes to a stop and holds the applied brakes on by virtue of sealing the hydraulic fluid in the lines out to the wheel brakes, the basic form being the "hold for 3 or 4 seconds only" for cars that don't have an electric handbrake, to the more useful version for cars that have an electric handbrake - which is the one that holds "for ever" and brings on a green handbrake light.

The only other function that gets called, or can be called "hill hold" is an internal function of auto trans which - which obviously man trans cars never have.

Edit:- as far as I can work out, nothing that I wrote gets altered by your posting - correct me if I'm wrong though.

 

[cairus]

You're confusing a lot of things here. Vehicles without an electric parking brake with manual transmission can also start uphill without rolling backward. It's called HHC. Our Octavia 3 has it in the family. Auto Hold is an extension of the electric parking brake. Quote: It prevents the vehicle from rolling away when stationary or starting off.

This happens when the Auto Hold function stores the last brake pressure applied when the vehicle is brought to a stop.

If the foot is removed from the brake pedal when starting off, all four wheel brakes remain initially applied. If the driver now presses the accelerator pedal (release the clutch with a manual transmission), the Auto Hold function releases its brake pressure. However, if the vehicle starts to roll without the driver pressing the accelerator pedal or clutch, the ABS activates and increases the braking torque so that the vehicle comes to a stop again. End of quote.

 

[cairus]

Addition: HHC depends on the installed ABS block, because the position sensor has to detect an upward slope. Auto Hold doesn't care.

 

[RUM4MO]

Addition: HHC depends on the installed ABS block, because the position sensor has to detect an upward slope. Auto Hold doesn't care.

I think that I know all of that, I tried to group all "hill hold" etc functions under one name while explaining the main differences, I've had a car with proper Hill Hold for 12 years and one with "Hill Hold Lite" for 10 years.

This discussion started out to highlight the possible annoyance caused by the brake lights being "on" while the car was being held stationary with the green handbrake light "function", I didn't consider that there was any need to split hairs and so dissect what I had written to "prove a point" , but there you go.

 

[cairus]

I know what you mean, but there are differences. That's why each system is called what it is. Because with active HHC, I've never noticed a brake light.

I think this is not splitting hairs if you stick to "facts"