Auto Hold function retrofit
#12
AudiWorld Member
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Saw some discussions a while ago regarding retrofitting the Auto Hold function. I put sometime looking into it and got it done last week.
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Once the wiring is done, turn on ignition and the headlight, the Auto Hold button should light up (the 'A' should light up). But if press on it, the red light would light up, but it doesn't stay there, it turns off immediately. That's because the Auto Hold function is not enabled yet.
Coding is needed in [09] Central Electrics and [03] Brakes. There is one bit in [09] and two bits in [03] that needed to be changed to fully activate the Auto Hold function. The change in [09] marks the Auto Hold button as 'installed', the changes in [03] actually turn on the Auto Hold functionality. Although I'd love to, but pardon me that I can't put up more coding details here in public, other vendors might beat me up![Frown](https://www.audiworld.com/forums/images/smilies/frown.gif)
After the coding and putting everything back. The project is done. Total time would be about 2 to 3 hours is taking slowly and carefully.
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See ya.
Steven
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Once the wiring is done, turn on ignition and the headlight, the Auto Hold button should light up (the 'A' should light up). But if press on it, the red light would light up, but it doesn't stay there, it turns off immediately. That's because the Auto Hold function is not enabled yet.
Coding is needed in [09] Central Electrics and [03] Brakes. There is one bit in [09] and two bits in [03] that needed to be changed to fully activate the Auto Hold function. The change in [09] marks the Auto Hold button as 'installed', the changes in [03] actually turn on the Auto Hold functionality. Although I'd love to, but pardon me that I can't put up more coding details here in public, other vendors might beat me up
![Frown](https://www.audiworld.com/forums/images/smilies/frown.gif)
After the coding and putting everything back. The project is done. Total time would be about 2 to 3 hours is taking slowly and carefully.
...
See ya.
Steven
I wonder if I can avoid installation of button and just do the coding to have it always enabled?
boshiku
#13
AudiWorld Member
#14
AudiWorld Super User
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The difference is, at least in my BMW, when you press that button the car will automatically hold on a hill every time you stop - without any further action on the part of the driver - until you press the button again. This is convenient in stop and go traffic, or just to ensure that your car doesn't roll forward or back after you stop, without having to engage the emergency brake every single time you stop. That's the difference. And apparently Audi thought it was convenient enough that they provide it as an option on every other Q7 in the world except for the US (and maybe Canada, although they seem to get other goodies we don't) - as do many other car manufacturers. Definitely a first-world problem, but so is ACC, four-wheel steering and many other convenience and safety options Audi DOES provide. And the place for the button IS ALREADY THERE, as are the fake bumper cutouts for headlight washers for cars not equipped with Night Vision.
#15
Banned
Thread Starter
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Likewise, you could set the two bits in [03] brakes to ‘enable’ the Auto Hold function, but the Auto Hold wouldn’t engage until you activate it through the button.
While Auto Hold works well most of the time, you would need the ability to disable it in some circumstances. For example, if you need to park into a very tight spot on the side of the street and there are cars in front and back of you, you would like to disable the Auto Hold so you can slightly release the brake and roll the car forward really slowly. With Auto Hold engaged, this is hard to achieve.
Hope this makes sense.
#17
Banned
Thread Starter
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The retrofit needs to drill holes and put in two additional sensors on the front sides and two on the rear sides. And run the wires as well as replacing the control panel, then coding. Price of the parts are not expensive, somewhere around $700, but the labor and time are excessive, and most people wouldn't even consider it. So we put it down.
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#18
AudiWorld Senior Member
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In US Q7s, if you engage the parking brake, when you step on the gas, the parking brake automatically disengages. What's the difference?
Also, if you have Adaptive Cruise Control (ACC), you can engage that with your foot on the brake (no car in front of you). You can then release the brake and car will not go until you either step on the gas or give a tug on the ACC lever.
So, not sure why this is needed.
Also, if you have Adaptive Cruise Control (ACC), you can engage that with your foot on the brake (no car in front of you). You can then release the brake and car will not go until you either step on the gas or give a tug on the ACC lever.
So, not sure why this is needed.
The difference is, at least in my BMW, when you press that button the car will automatically hold on a hill every time you stop - without any further action on the part of the driver - until you press the button again. This is convenient in stop and go traffic, or just to ensure that your car doesn't roll forward or back after you stop, without having to engage the emergency brake every single time you stop. That's the difference. And apparently Audi thought it was convenient enough that they provide it as an option on every other Q7 in the world except for the US (and maybe Canada, although they seem to get other goodies we don't) - as do many other car manufacturers. Definitely a first-world problem, but so is ACC, four-wheel steering and many other convenience and safety options Audi DOES provide. And the place for the button IS ALREADY THERE, as are the fake bumper cutouts for headlight washers for cars not equipped with Night Vision.
However, what Rick said, I never thought of using it, because I thought it will keep going. I did use it with traffic jam assist on ACC with a car in front of me at red light, but I didn't think there would be a way to use ACC to hold the Q7 in place at red light with no cars in front. Does this activate brake lamps? I have to try this, so you come to a stop at red light, keep pressing brake, activate ACC and then let go of brake?
If my Q7 wasn't a lease, I'd be doing this immediately.
#19
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[QUOTE=hayde_bre;25202653
However, what Rick said, I never thought of using it, because I thought it will keep going. I did use it with traffic jam assist on ACC with a car in front of me at red light, but I didn't think there would be a way to use ACC to hold the Q7 in place at red light with no cars in front. Does this activate brake lamps? I have to try this, so you come to a stop at red light, keep pressing brake, activate ACC and then let go of brake?
[/QUOTE]
Yes, it works with ACC ON as you described. I don't know if the brake lights are on in this case (never paid attention) but I know that the brake stays pressed in this case so I would assume the red lights are on.
However, what Rick said, I never thought of using it, because I thought it will keep going. I did use it with traffic jam assist on ACC with a car in front of me at red light, but I didn't think there would be a way to use ACC to hold the Q7 in place at red light with no cars in front. Does this activate brake lamps? I have to try this, so you come to a stop at red light, keep pressing brake, activate ACC and then let go of brake?
[/QUOTE]
Yes, it works with ACC ON as you described. I don't know if the brake lights are on in this case (never paid attention) but I know that the brake stays pressed in this case so I would assume the red lights are on.