XC60 Start/Stop and Hill Start Assist

[Stevepvolvo]

Originally Posted by Rex65

I had a quick look but I can't seem to find the setting now, weird!
I'll look again but I did have a software update at a recent service, so wonder if it's been deleted now?

Thanks for checking. I rechecked all my setting options and couldn't find one for eco mode. As you say maybe removed for some reason in a software update.

[Julianpms]

Originally Posted by Stevepvolvo

Dear Members
I have an MY2016 XC60 Auto with start/stop. My braking method is progressive braking and I have noticed that the engine stops before the vehicle is stationary. I do not have an ECO button that on some models states that with this button on then the engine may cut out before the vehicle is stationary. By itself that would not be a concern. However, I have noticed that the Hill Start Assist function that should maintain braking for up to 2 secs when the engine is off to allow the driver to transfer their foot from the brake to the accelerator, does not always activate and on hills I start to roll backwards until the engine restarts. I know the HSA does work as if I stop abruptly then it activates. I have contacted Volvo support and they have provided a detailed explanation of the Hill Start Assist (HSA) function and it clearly states that the engine must be running when the brakes are applied, and the vehicle comes to a complete standstill.
My question to the members is whether others with the same vehicle have experienced the engine in start/stop mode cutting out whilst still braking resulting in “coasting”. If not it may be that the speed sensor for the engine cut-off is incorrect as I have not found any other setting that would change the behaviour of the stop speed such as an ECO button.
Your observations appreciated
Steve

Wrt your issue of the car rolling back when re-starting on an uphill slope, I have occasionally experienced this on my V60 and now V40. To overcome this, I manually switch off the Start/Stop function just as the traffic ahead of me starts to move off: with the engine running the transmission is then in Drive, thus providing a little 'creep', enough to overcome the slight tendency to roll backwards.

[MikeIOW]

Originally Posted by Stevepvolvo

Dear Members
I have an MY2016 XC60 Auto with start/stop. My braking method is progressive braking and I have noticed that the engine stops before the vehicle is stationary. I do not have an ECO button that on some models states that with this button on then the engine may cut out before the vehicle is stationary. By itself that would not be a concern. However, I have noticed that the Hill Start Assist function that should maintain braking for up to 2 secs when the engine is off to allow the driver to transfer their foot from the brake to the accelerator, does not always activate and on hills I start to roll backwards until the engine restarts. I know the HSA does work as if I stop abruptly then it activates. I have contacted Volvo support and they have provided a detailed explanation of the Hill Start Assist (HSA) function and it clearly states that the engine must be running when the brakes are applied, and the vehicle comes to a complete standstill.
My question to the members is whether others with the same vehicle have experienced the engine in start/stop mode cutting out whilst still braking resulting in “coasting”. If not it may be that the speed sensor for the engine cut-off is incorrect as I have not found any other setting that would change the behaviour of the stop speed such as an ECO button.
Your observations appreciated
Steve

Ours is MY14.5...not entirely sure what you mean when you say "My braking method is progressive braking", but I haven't found any issues with HSA over 50K miles.
Sometimes the engine will stop before I am at a complete halt with the stop-start, but I've never found that to be an issue.
If I am in busy stop-start traffic maybe I will turn it off, but not normally - mind you, I also have the adaptive cruise, & that doesn't stop the engine, & probably 70% of the time I will be using that (great in traffic as well as on motorways!).

Just an alternative viewpoint - it sounds like a few of you have issues that are perhaps a little alarming, but they are not necessarily 'across the board'.

[Stevepvolvo]

Hi Julinpms, yes that is a way around the issue. I just never quite know whether HSA will be active until I take my foot off the brake. As the particular circumstances are a long up hill run of over 0.5 miles in very slow stop start traffic then I probably stop every 10m so end up just switching off the system or using Queue Assist. Whilst both get around the issue it a) results it negates the advantages of start/stop b) I don't understand why Volvo don't set the speed cut-off limit to zero as this would negate the problem. Even in the manual I have noticed that it states - "For certain engine variants the engine may auto-stop before the car is stationary regardless of whether the ECO function is activated" - so it seems that it is intentional regardless of whether you have an ECO button and turn it off to prevent it. I have written to Volvo this am to see if they will shed any further light on the reasoning and whether if going down hill in slow traffic resulting in the engine cutting out whether the brake servo will eventually discharge. If so that seems a rather risky function to build in and the engine should only cut out at zero mph. I am probably over thinking this but would be interesting to know the reasoning

[Stevepvolvo]

Originally Posted by MikeIOW

Ours is MY14.5...not entirely sure what you mean when you say "My braking method is progressive braking", but I haven't found any issues with HSA over 50K miles.

Hi MikIOW - basically it means I predict the stopping of traffic, apply firm braking early to shed most momentum off the vehicle but then lift off the brakes maybe 5m before I need to stop and am then only travelling at maybe a couple of mph and so most of the momentum is removed from the vehicle and I almost "coast" to a stop. A technique I was taught as more comfortable for passengers. So for the last 5m the engine cut-out and so doesn't activate HSA. If I brake "normally" then HSA does activate but my wife complains as my braking is aggressive in her opinion
So you are correct it is more about braking technique and HSA activation parameters than an across the board problem

[Fursty Ferret]

You can tell if HSA is engaged if you maintain moderate pressure on the pedal after the car has stopped. About 0.5 to 1 second later you'll feel a "click" through the pedal and the pressure under your foot will decrease very slightly.

Can't say I've ever expected it and not found it there, but on gentle slopes where it's not quite steep enough to engage it is a little disconcerting when the car rolls back a fraction.

Could engage the handbrake if you're in doubt as it'll release automatically when you press the accelerator?