Auto Stop/start with Auto Hold activated

[Sherwood]

Now here is an interesting observation. I was out in the XC40 earlier today and the Auto Stop/start was working exactly as it should. I had Auto Hold activated and it was auto-starting when I depressed the accelerator pedal. Weird, I thought. Has the problem cured itself? Later though the problem returned and it was auto-starting as soon as I released the brake pedal.

What was different to cause the change in behaviour? The only thing I could come up with was that I had activated the speed limiter. I then tested it. With Auto Hold engaged I stopped the car around 20 times. If the speed limiter was off, it auto-started when I depressed the accelerator pedal (as it should according to the manual). If the speed limiter was engaged, it auto-started as soon as I released the brake pedal. This behaviour was consistent every time. Speed limiter off, auto-start works as per manual. Speed-limiter on, auto-start behaviour changes.

Googling the problem brought me back to this forum and a thread from 2019
viewtopic.php?t=1355

Are you using the speed limiter? There's a bug* with the system where the engine restarts immediately when the brake pedal is released in auto-hold if the speed limiter is active.
* I say "bug", Volvo told my dealer it's meant to happen but declined to provide a reason.

Looks like this is the answer, or at least an answer.

Apologies for resurrecting this post, but has anyone got any idea whether this particular issue has/should have been resolved?

My 4-week old car has been in to the dealers today for diagnosis/resolution of exactly this issue, but unsuccessfully. "It's all working as designed, though they have played around with the stop/start software quite a bit just recently".

As I tend to use the speed limiter as a matter of habit, I find it astounding and disturbing that its setting can have such an effect on an unrelated function such as Start/Stop. (it's also rather annoying, since in many circumstances it renders the proper use of one or other of the functions impossible).

I've raised the issue with Volvo Customer Services, but it would be useful to know whether there is already a fix, and just how many people have the same symptoms.

[Norton]

My XC40 still does this and it has had several software upgrades since I first reported the problem, first to the dealer and then to Volvo UK customer service. And every other XC40 I have driven in the past 12 months (there have been a lot of courtesy cars!) has had the same problem.

I think it must be a bug in the car’s software, and a bug which is difficult to fix as it has been ongoing for so long. I think you will find that every XC40 does this.

I too was astonished that a car of the sophistication of the XC40 had such a problem. And it is annoying as an urban environment with lots of stopping at traffic lights is also where I am likely to be using the speed limiter. My routine now on approaching a stop is to disengage the speed limiter. As soon as the stop/start has turned off the engine I can then re-engage the speed limiter and the engine stays off.

[Sherwood]

My routine now on approaching a stop is to disengage the speed limiter. As soon as the stop/start has turned off the engine I can then re-engage the speed limiter and the engine stays off.

...yup, I've already resorted to that (you can actually wait until you've fully stopped and then disengage before releasing the footbrake) - which is Ok-ish (if you remember to re-engage ).

Looks like I'm going to have to keep on at Customer Services (or higher).

[xbimmer]

I had this problem for around 18 months. At recent service, having pointed out the problem again, was told battery needs to be above 70% for stop start to activate. I had just done 500 miles the previous week so the battery was either full or faulty. Lo and behold on picking up the car the stop start worked Ok even with auto hold (not sure what the garage did though). After parking overnight the problem came back until I had done around 80 miles. I suspect the battery but the garage said it was OK. Maybe a trickle charger is the answer?

[Sherwood]

I don't think this is the same issue.

Stop/Start and Auto-hold work perfectly, and as expected, on mine, unless the speed-limiter is engaged, in which case they don't play together properly.

[xbimmer]

I never use speed limiter so that's not my issue.