Problem with autohold

[Live4USMC]

My x5 50i lurches forward approximately 6” when I’ve come to complete stop with the auto hold on and then let off of the brake pedal. It stops again on its on and stays stopped. This is a recent development and I was wondering if anyone else has had similar issues and if the dealer has been able to rectify this.
Thanks

[spike5150]

Mine had done this since day one. Is more pronounced the colder it gets. Dealer has been unable to reproduce, so I have had to live with it for 57,000 miles and counting. June 2015 50i.

[Live4USMC]

Originally Posted by spike5150

Mine had done this since day one. Is more pronounced the colder it gets. Dealer has been unable to reproduce, so I have had to live with it for 57,000 miles and counting. June 2015 50i.

Mine is temperature dependent as well. It was 65 degrees today and it worked fine. Cold weather seems to cause this issue.

[turboawd]

What exactly is holding the vehicle? Parking brake? One of the calipers?

[CeeTeeX5]

Tried the auto hold for the first time this morning in 38f temperature and no lurching forward. Maybe this was fixed in a sw update?

[spike5150]

Originally Posted by CeeTeeX5

Tried the auto hold for the first time this morning in 38f temperature and no lurching forward. Maybe this was fixed in a sw update?

My wife's 35i built one month later does not exhibit this problem.

[CeeTeeX5]

Originally Posted by spike5150

My wife's 35i built one month later does not exhibit this problem.

Interesting, might just be a 50i issue. All those ponies just don't want to be held back!

[IndyJer]

Originally Posted by turboawd

What exactly is holding the vehicle? Parking brake? One of the calipers?

Parking brake.

I keep the brake pedal pressed until I feel the parking brake engage and then lift off. No lurching for me.

[DuSh]

Originally Posted by IndyJer

Parking brake.

I keep the brake pedal pressed until I feel the parking brake engage and then lift off. No lurching for me.

Are you certain? I've read that Auto Hold uses regular brakes and NOT parking brake (which makes sense btw as parking brake is too slow to engage and disengage to be used constantly in stop and go traffic). I've heard that Auto hold only uses parking brake as a failsafe last option

[IndyJer]

Originally Posted by DuSh

Are you certain? I've read that Auto Hold uses regular brakes and NOT parking brake (which makes sense btw as parking brake is too slow to engage and disengage to be used constantly in stop and go traffic). I've heard that Auto hold only uses parking brake as a failsafe last option

As certain as anything else you hear on the inter webs... I’ve not looked at the regular brakes with auto hold engaged to see if they’re used, but I am assuming it’s the parking brake since the parking brake symbol lights on the dash when autohold is engaged and the vehicle is at a stop. See near the 2:37 mark of the video...

[absolutegtr]

I believe the autohold uses the front brakes. I say this because just once there was a minor glitch when using the autohold in heavy traffic. And I tried to accelerate and I could feel the front brakes still grabbing. (Happened very quickly)

Also in my X5 with ACC STOP AND GO the car will stop itself and hold itself stopped by itself using (obviously) the front brakes.

[CatalinP]

Automatic hold function

The automatic hold function is activated using a button behind the parking brake button. The button is connected to the Dynamic Stability Control (DSC). When the function is selected, the vehicle is hydraulically braked from the first application of the brake by the DSC until it comes to a complete halt. When the engine is switched off, the parking brake assumes the holding function.

Pressing the accelerator pedal releases the wheel brakes. The vehicle begins to move. The automated braking and release process supports driving in urban traffic or in jams, for example. Automatic releasing of the brake is also possible outside the automatic hold function.

https://www.newtis.info/tisv2/a/en/f...-brake/XokjYm0

[CatalinP]

Originally Posted by absolutegtr

I believe the autohold uses the front brakes.

Also in my X5 with ACC STOP AND GO the car will stop itself and hold itself stopped by itself using (obviously) the front brakes.

That is not true. While the engine is running, the brakes are automatically applied to all 4 wheels. If the engine is stopped, then the "hand brake" is engaged on the rear wheels.

[DuSh]

Originally Posted by CatalinP

That is not true. While the engine is running, the brakes are automatically applied to all 4 wheels. If the engine is stopped, then the "hand brake" is engaged on the rear wheels.

That makes sense - all 4 brakes for autohold and parking brake if engine is off (since pump is not working for regular brakes with engine off). So any surging forward like OP has during autohold is due to either bad sensor or some module or worn brakes (highly unlikely that all 4 brakes get so worn that they can't hold on autohold)

[spike5150]

I’ve got mine in for scheduled maintenance and asked them to look at the auto hold again. It’s in the 20’s here so they better be able to reproduce it this time. Will let you know if they figure it out.

[spike5150]

Well they were able to reproduce the problem but no clue hoe to fix it. They are starting a PuMa case with BMW so my x5 is a hostage for the weekend.

[absolutegtr]

Originally Posted by CatalinP

That is not true. While the engine is running, the brakes are automatically applied to all 4 wheels. If the engine is stopped, then the "hand brake" is engaged on the rear wheels.

Right.....That’s exactly what I just said...

Edit* and by ‘front’ brakes I was implying all 4 wheels and NOT the handbrake. This system is quite similar to the Mercedes HOLD function

[CatalinP]

Yeah, right, front brakes = all 4 wheels.

[spike5150]

Originally Posted by spike5150

Well they were able to reproduce the problem but no clue hoe to fix it. They are starting a PuMa case with BMW so my x5 is a hostage for the weekend.

Update - They said the problem is with the DSC and Hydraulic module. Special order parts from Germany +/- 2 weeks. I get the car back this afternoon for now - will try to get the PUMA case number for others with this issue to reference.

[spike5150]

Originally Posted by Live4USMC

My x5 50i lurches forward approximately 6” when I’ve come to complete stop with the auto hold on and then let off of the brake pedal. It stops again on its on and stays stopped. This is a recent development and I was wondering if anyone else has had similar issues and if the dealer has been able to rectify this.
Thanks

Hope it helps you out - my PUMA case # is 64073055. Now waiting on parts from Germany for +/- 2 weeks, so not necessarily resolved yet. My paperwork says it is $4,000 worth of parts, but covered under warranty since I first brought up the issue when I was still in warranty.

[spike5150]

Well, they replaced the DSC stuff and still not fixed. Had a Regional Tech look at it today, and he claims it is normal. I am calling BS on that! Might have to escalate to BMWNA.

[utsc]

Originally Posted by spike5150

Well, they replaced the DSC stuff and still not fixed. Had a Regional Tech look at it today, and he claims it is normal. I am calling BS on that! Might have to escalate to BMWNA.

Did you get the problem resolved ?