Stop/Start system not working

[Mint Cake]

In 4 months of ownership, my stop start has worked once.
It's a "feature" that I'm very happy for it not to work. When I borrow Mrs Mintcake's car its a PITA when the engine cuts out on you, just as you're about to pick up on a gap whilst entering a roundabout !

[KNVXC90]

My Stop/Start used to work flawlessly. but the car usage has drasticaly gone down since the beginning of pandemic. I am just beginning to drive a bit more and the Stop/Start is no longer working.

I did drive 2.5 hours to Birmingham and another 2.5 hours back to Chelmsford, but that still didn't help.

[Lolow2011]

I think it’s characteristic of some stop start systems, temperamental. In my discovery sport it worked only a handful of times, out of the blue, over the many years of ownership. It never seem to be correlated to the so called optimal conditions of full battery, ambient temp, braking etc.

Stop start worked flawlessly, even in freezing cold, with AC on, wipers heaters etc in my BMW 4 Gran Coupe.

[ThomasC91]

I stand to be correct because I could be wrong, but DPF can cause stop/start not to work...again this would be due to the car not being driven long enough or at high enough speed to clear the filter. It gets blocked. I think I have read somewhere this can make the stipy/start not work.

Get some cataclean or hydro blast and see if that works.

Even if it doesn't resolve it, it will still clean your pipes, DPF etc.

[ThomasC91]

To also there's positives to it not working.

When it works flawlessly the car is constantly stopping and starting which is A LOT of wear and tear.

Shame there's not a single button to turn it off and you have to go into sensus

[Backinavolvo]

It's a handy feature that you can move icons about..

I have a perfect muscle memory now for swipe to right, and tap the stop start top right!

[Zebster]

Originally Posted by ThomasC91

I stand to be correct because I could be wrong, but DPF can cause stop/start not to work...again this would be due to the car not being driven long enough or at high enough speed to clear the filter. It gets blocked. I think I have read somewhere this can make the stipy/start not work.

Get some cataclean or hydro blast and see if that works.

Even if it doesn't resolve it, it will still clean your pipes, DPF etc.

On mine when it's a DPF issue then the 'engine system' is flagged as the reason for stop/start unavailability when drilling down into the Sensus eDrive menu.

But the problem with stop/start unavailability on mine is almost always the 'electrical system' and charging the battery overnight fixes it (at least temporarily). I am convinced that anything other than a brand new battery will cause this problem, especially when lockdown is causing reduced usage.

[crashbarrier]

I am definitely beginning to realise that it's fairly normal with Volvo for the system not to work as it should do. Personally, I agree with ThomasC91 that constantly stopping and starting must have a detrimental effect on the mechanicals of the car; I think many of us remember the days when starter motors were less than reliable and a good whack with a hammer would sort most issues but not this car though. I tend to always turn the system off but recently felt that we should use it as intended to make sure that it is working correctly, which it isn't. I think I'm going to put it down to one of those things as I can sense a bill coming from the dealer when they say it doesn't fall under the warranty.

Interestingly, my BMW with the faultless stop/start system is also a 4 series Gran Coupe like Lolow2011.

With regards to the DPF I am surprised that the car is not throwing up a warning that things are amiss if it is beginning to affect other systems. I will investigate the suggestion of an additive to clear things out.

Thanks for all the replies so far

[Zebster]

Originally Posted by crashbarrier

I am definitely beginning to realise that it's fairly normal with Volvo for the system not to work as it should do. Personally, I agree with ThomasC91 that constantly stopping and starting must have a detrimental effect on the mechanicals of the car; I think many of us remember the days when starter motors were less than reliable and a good whack with a hammer would sort most issues but not this car though. I tend to always turn the system off but recently felt that we should use it as intended to make sure that it is working correctly, which it isn't. I think I'm going to put it down to one of those things as I can sense a bill coming from the dealer when they say it doesn't fall under the warranty.

Interestingly, my BMW with the faultless stop/start system is also a 4 series Gran Coupe like Lolow2011.

With regards to the DPF I am surprised that the car is not throwing up and warning that things are amiss if it is beginning to affect other systems. I will investigate the suggestion of an additive to clear things out.

Thanks for all the replies so far

The DPF should not be a concern. During lockdown I've done mostly short journeys only and so have been checking the DPF soot loading using diagnostic equipment and it's hardly even reached around 50% loading at worst (12.5g Vs ~26g where active regeneration is triggered). Passive regeneration works exceptionally well on mine and I'd suggest you don't worry at all. Even if it did get bad and flag a warning then you'd just need to take it for a motorway cruise lasting 30 minutes or so. Personally I would advise against using additives for this purpose.

[ThomasC91]

I personally use an additive because it’s cos5 effect against using premium fuel.... I beli3ve adding additive is the equivalent and yet a lot cheaper.

It supposedl6 improves mpg too.