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jmr99vet
01-20-2011, 03:27 PM
Have had my 535 for 5 months and the function has never been on. I decided to look up the auto hold function in the book. I must be missing something as the only thing that the book said was it would be good to use on a hill and in traffic. When I am on a hill or in traffic with the transmission in D my foot is on the brake. What am I missing? Thanks

baloo588
01-20-2011, 03:31 PM
Haha. You are not turning on the auto hold button which is near your center arm rest that says Auto H. Press it down to turn it on and it will work.

tdepetra
01-20-2011, 03:33 PM
The idea is for you to be able to not have to hold your foot on the brake, but have the hold feature do it for you. Then, when the light turns green, your foot on the accelerator releases the hold feature.

jmr99vet
01-20-2011, 03:35 PM
The idea is for you to be able to not have to hold your foot on the brake, but have the hold feature do it for you. Then, when the light turns green, your foot on the accelerator releases the hold feature.
Thanks for the explanation. Do you use it on a regular basis?

Mr. Magic
01-20-2011, 03:39 PM
Take your foot off the brake and the car will roll on the hill while in Drive or Reverse. In the short time it takes to move your foot to the accel. pedal and the car to respond, you can roll a short distance and bash into something.

The auto hold will keep the brake applied until the car starts to respond from the accelerator. It's nicer and safer than using 2 feet (one on brake, one on accel.), or to quickly move your foot over and punch down. I used it the other day when backing out of a steep hill with a metal pole a foot or so in front of me. There was no short roll forward - it just went backwards in reverse when I backed out. Nice.

tdepetra
01-20-2011, 03:42 PM
Thanks for the explanation. Do you use it on a regular basis?

Rarely use it, but when I do, it's great to have.

jmr99vet
01-20-2011, 03:47 PM
Rarely use it, but when I do, it's great to have.

I will use it as needed.

laser
01-20-2011, 04:23 PM
You are not missing something, I have the same question.

It's really an oddity to have this with the AT ......... I wish I had with an MT as Atlanta is a hilly city and it would be quite useful for starting uphill. :dunno:

Never use it.

Erregend
01-20-2011, 04:58 PM
I wish I had with an MT as Atlanta is a hilly city and it would be quite useful for starting uphill.

Am I missing something? Doesn't MT 535 have the same function as MT 335 which holds car on a hill from rolling backwards for ~3 seconds after releasing the brake, giving you time to let out the clutch and start moving forward???

laser
01-20-2011, 05:02 PM
We don't have MTs, but with ATs have the auto hold feature which is straight from the department of redundantcy department.

This a great feature on an MT.

bimluva
01-20-2011, 05:30 PM
It's handy in traffic where it's stop and go or at red lights.

ihumphrey
01-20-2011, 05:30 PM
We don't have MTs, but with ATs have the auto hold feature which is straight from the department of redundantcy department.

This a great feature on an MT.

I disagree! I love this feature and use it in traffic all the time. You needn't keep your foot on the brake all the time, keeps fatigue down when it is stop and go traffic or in an area with tons of stoplights.

TJPark01
01-20-2011, 05:34 PM
The BMW nomenclature is confusing people once again.
Drive-off assistant - After the foot brake is released, the vehicle is held in place for approx. 2 seconds (page 98) Keeps you from rolling backwards on a hill.
Automatic Hold - This system assists the driver by automatically setting and releasing the parking brake, such as when moving in stop and go traffic. (page 60) * Only automatics have this.

markl53
01-20-2011, 05:55 PM
Automatic Hold - This system assists the driver by automatically setting and releasing the parking brake, such as when moving in stop and go traffic. (page 60) * Only automatics have this.

Actually, though it lights up a green version of the parking brake indicator on the dashboard, I've determined that Auto Hold does not rely on the parking brake. When you apply the parking brake you can hear it (window open) and feel it in the brake pedal. When auto hold is engaged, I believe it's "just" a system which keeps the regular brake calipers gripping the disks. Also the brake lights remain lit while it is holding the car. With a little more experimentation I think you'll find the parking brake is not applied at each stop. Though, if auto hold is engaged, the parking brake will be applied (and the red light will come on) when you shut off the car.

markl53
01-20-2011, 06:00 PM
We don't have MTs, but with ATs have the auto hold feature which is straight from the department of redundantcy department.

This a great feature on an MT.

As others stated, Auto Hold is different from hill assistant. With auto transmission, as well as an MT, you will roll forward down a hill if you don't keep your foot on the brake. Auto Hold removes the need for you to keep your foot on the brake pedal. It will hold the brakes in place until you touch the accelerator. Completely different function than hill assistant.

TJPark01
01-20-2011, 06:05 PM
Actually, though it lights up a green version of the parking brake indicator on the dashboard, I've determined that Auto Hold does not rely on the parking brake. When you apply the parking brake you can hear it (window open) and feel it in the brake pedal. When auto hold is engaged, I believe it's "just" a system which keeps the regular brake calipers gripping the disks. With a little more experimentation I think you'll find the parking brake is not applied at each stop. Though, if auto hold is engaged, the parking brake will be applied (and the red light will come on) when you shut off the car.

Yes you can hear the parking brake being applied when you engage it manually and also feel it under your foot as you describe. But the lack of audible and sensory indications does not mean the AutoHold system is operating using the regular brake calipers. What I wrote is verbatim from the owners manual. What you're describing is anecdotal evidence. I'm not saying you're wrong, in fact, I had no idea how it worked. I'm just referencing the manual and not my own perceptions, which is why I wrote the page #'s on there.

Needsdecaf
01-20-2011, 06:20 PM
I have a hard time believing that it uses the parking brake. I know that's what it says, believe me. But think about it. THe parking brake is slow to release. Takes 1-2 seconds? The automatic hold releases much more quickly.

Also, I would tend to believe that cycling the parking brake that many times (could it be dozens, if not hundreds of times on one trip) would have a serious effect on the life of the parking brake mechanism.

TJPark01
01-20-2011, 06:26 PM
I have a hard time believing that it uses the parking brake. I know that's what it says, believe me. But think about it. THe parking brake is slow to release. Takes 1-2 seconds? The automatic hold releases much more quickly.

Also, I would tend to believe that cycling the parking brake that many times (could it be dozens, if not hundreds of times on one trip) would have a serious effect on the life of the parking brake mechanism.

I thought it was either through the tranny, or like you said, regular brakes. Honestly, I never thought about it till this thread. I'm sure there is a way to find out, but it involves a lot more work than I'm willing to. Either way, during stop and go traffic, it lessens a laborious chore.

Rafa
01-20-2011, 07:18 PM
It is a great feature, regardless of which brake is applied. I use it much of the time on stop and go traffic and on inclines.

I agree with markl53: the auto hold uses the regular brakes.

eyesight1
01-20-2011, 08:20 PM
I also think it a great feature which I use from time to time. Sitting at a red light behind a lot of traffic or on a hill. Even just waiting for my wife to come out of a store works well. Just stop the car normally and take your foot off the break but stay still anyway. To move again just step on the as. Great, but simple feature.

ProRail
01-20-2011, 10:06 PM
Have had my 535 for 5 months and the function has never been on. I decided to look up the auto hold function in the book. I must be missing something as the only thing that the book said was it would be good to use on a hill and in traffic. When I am on a hill or in traffic with the transmission in D my foot is on the brake. What am I missing? Thanks

If you haven't missed it, don't worry about it. You don't need it.

Kar Don
01-20-2011, 10:09 PM
Salesman showed me autohold on the test drive, I loved it! But my question was does it keep the brake light on at a traffic light when you are stopped, I couldn't tell because it was super sunny out and got no reflections off the cars behind me.

raleedy
01-20-2011, 11:40 PM
Salesman showed me autohold on the test drive, I loved it! But my question was does it keep the brake light on at a traffic light when you are stopped, I couldn't tell because it was super sunny out and got no reflections off the cars behind me.

You could get out and check for yourself.

Needsdecaf
01-21-2011, 06:01 AM
Salesman showed me autohold on the test drive, I loved it! But my question was does it keep the brake light on at a traffic light when you are stopped, I couldn't tell because it was super sunny out and got no reflections off the cars behind me.

If I am not mistaken Markl posted before that yes, it does, as witnessed by reflections during morning commute.

Needsdecaf
01-21-2011, 06:02 AM
If you haven't missed it, don't worry about it. You don't need it.

Good philosophy.

markl53
01-21-2011, 06:27 AM
If I am not mistaken Markl posted before that yes, it does, as witnessed by reflections during morning commute.

You are right, though it was evening. I had also been curious but it makes sense so people behind you "think" you're still holding the brake. I only use A-H occasionally but it can be useful.

ihumphrey
01-21-2011, 07:19 AM
Yes, the lights stay on...and I am almost certain it is the parking brake and not the actual brake calipers...

jimefam
01-21-2011, 07:57 AM
I used it for a while in europe but I got the sensation when coasting as if it were slowing down the car. I don't know if it was all in my head but it sure felt like the car would slow down quicker with it on so I decided not to mess with it.

AzNMpower32
01-21-2011, 05:38 PM
The new electro-mechanical parking brake is what allows the Auto-H function. In a sense, it works in sync with the Park brake.

When it is on and engaged (illuminated green Park), the system uses the brake calipers and the brake lights remain illuminated, so it is as if you were pushing down on the brake pedal itself. Touching the throttle will release the brakes.

Similarly when the engine is running, engaging the Park brake (via pulling the dash switch) does the exact same thing, and Park illuminates in red. However, it won't automatically engage/release like Auto H- you have to push the button to release.

When the engine is turned off, the system defaults to the usual drum brakes like a traditional hand brake. Hence, there can be a jolt when turning off the engine with the Park Brake engaged as it transfers from disc to drum.

It's not the greatest thing since sliced bread, but quite useful in suburban or urban driving with frequent stops.

Zathris
01-21-2011, 06:52 PM
I enjoy the Auto H feature in stop and go traffic and use it quite a bit. I come from many years of driving a manual transition where I did not have the pull of the engine at a stoplight. For what ever reason, having to apply the extra pressure in an automatic to over come the pull of the automatic transition in drive annoys me. My options are, throw it in neutral or use the Auto H feature. I choose the latter and find it very convenient for fast take offs off the line.

-Zathris

markl53
01-21-2011, 08:10 PM
The new electro-mechanical parking brake is what allows the Auto-H function. In a sense, it works in sync with the Park brake.

When it is on and engaged (illuminated green Park), the system uses the brake calipers and the brake lights remain illuminated, so it is as if you were pushing down on the brake pedal itself. Touching the throttle will release the brakes.

Similarly when the engine is running, engaging the Park brake (via pulling the dash switch) does the exact same thing, and Park illuminates in red. However, it won't automatically engage/release like Auto H- you have to push the button to release.
AzN, you tend to be very confident in your statements, as fact, with little room, IMO, for doubt. After driving my 535i for 4 months, I've come to some of my own conclusions based on easily discernable observations. Manually engaging the parking brake, by pulling the brake control lever while the engine is running, results in a definite motor sound of the parking brake applying as well as a "sinking" feeling while holding the service brake pedal down. Similarly. you can hear and feel the parking brake release by listening and feeling the response in the brake pedal. Neither of these actions occur when Auto Hold engages or disengages. It may in fact use part of the parking brake components, but IMO, it operates in a much different manner.

When the engine is turned off, the system defaults to the usual drum brakes like a traditional hand brake. Hence, there can be a jolt when turning off the engine with the Park Brake engaged as it transfers from disc to drum.

Not sure where you're getting this, I have absolutely no "jolt" when I turn my car off after the parking brake has been applied.

Remind me, you actually own an X3, correct? Is it your Mom who has the F10 that you drive once in a while?

markl53
01-21-2011, 08:17 PM
I used it for a while in europe but I got the sensation when coasting as if it were slowing down the car. I don't know if it was all in my head but it sure felt like the car would slow down quicker with it on so I decided not to mess with it.

When I have Auto Hold activated, I sometimes am in heavy traffic. I can slow down to a crawl, like 1 mph or less, and AH only takes effect after the car comes to a complete stop.

AzNMpower32
01-21-2011, 09:16 PM
Remind me, you actually own an X3, correct? Is it your Mom who has the F10 that you drive once in a while?
Pops has an X5 35d which I've driven before. That's how Auto H works on the X5, although admittedly I prefer manually engaging/disengaging the park brake. The transition to the drum brakes isn't always noticeable, more so when parked on a gradient.

In both cases with the engine on, where either Auto H is engaged, or the park brake is engaged, the brake pedal feels noticeably different as you mentioned, as if the service brake pedal is "held".

Granted, it's in the shop more often than not.

markl53
01-21-2011, 09:23 PM
Pops has an X5 35d which I've driven before. That's how Auto H works on the X5, although admittedly I prefer manually engaging/disengaging the park brake. The transition to the drum brakes isn't always noticeable, more so when parked on a gradient.

In both cases with the engine on, where either Auto H is engaged, or the park brake is engaged, the brake pedal feels noticeably different as you mentioned, as if the service brake pedal is "held".

Granted, it's in the shop more often than not.

Maybe they've change how the 5's version works a bit. I don't feel anything in the brake pedal when AH engages. I'm talking about if you are holding the pedal when you manually set the parking brake, the brake pedal sinks a bit, very noticeable. Doesn't happen with AH.

2008550I
01-21-2011, 09:25 PM
It's handy in traffic where it's stop and go or at red lights.

:thumbup:That's when I use it. Also while sitting in any kind of long line.