Anyone know what the dependancies/logic is for the Start/Stop to work?

 

Sometimes it switches the engine off about 2 minutes down the road from my house, sometimes it doesn't.  The other day I dropped a friend off, sat outside his house, engine stayed on.  We chatted in the car for a bit, 5-10 min later it turned off.

Then, it randomly restarted about 5 minutes later....

 

The only thing I know stops it is the air-con.  If it still needs engine power to get to the set temp, it'll force it to stay on.  Likewise, if you turn the aircon on while sat there, the engine will restart.

Obviously, the clutch, turning the wheel etc, rolling more than ~2mph etc too, but I mean the less obvious/visible stuff when you're sat stationary not touching anything.

 

Sometimes it's totally predictable, sometimes it just doesn't turn off and I can't figure out why....  clearly it's waiting for something and it bugs me not knowing why.

 

Alex

The battery’s state of charge is another factor.

 

Gaz

Strange but true, the Owners Manual tells people that read the relevant section the reasons that Stop / Start might do what it does under various conditions.

Battery demand / Load,  Temperature differences external and interior.

Then there are the many many threads on Stop / Start and why does it do what it does.

You can see the reason it is not switching off on the main screen. Sometimes it is heat or cold, sometimes humidity, sometimes electrics, the list is long.

 

Don't bother, it will not switch the car off if the conditions aren't met. 

 

 

Many threads, as said. Mine would not function at all until I got a new battery.

10 hours ago, gregoir said:

Many threads, as said. Mine would not function at all until I got a new battery.

Because "it's simply clever"

As above mine didnt work at all or for previous owner, had warranty batteryreplacement last week and it works perfect now, car is a 66plate pre f/l 230

So a search brings up over 2000 pages of anyone mentioning Start Stop and not found a useful one yet.  Anyone got a link?

 

Found a few talking about disabling it, but not just explaining what parameters it's looking for.

On 01/08/2019 at 08:09, Alex-W said:

waiting for something and it bugs me not knowing why.

 

Have to admit it doesn’t keep me awake not knowing things like this 🤔 but if you must:

 

1.Vehicle Speed (varies with s/s model year)

2. Engine speed (varies but generally below 1500rpm)

3. Coolant between 25 and 100 deg C

4. Brake vacuum greater than 550mb

5. Battery temperature between -1 and 55 deg C

6. Battery capable of starting voltage prediction 

7. Difference between commanded and actual cabin temperature less than 8 deg C

8. DPF not in regeneration mode.

 

There will be variances for different models and years but I hope that lets you sleep at night 😀

It doesn't help that the infotainment messages are cryptic, like Aircon engine needs to be running for stop start to work.

Even with a new battery I found I had to trickle charge the battery about once a week. The battery management system seemed to be over aggressive, about when to let the alternator kick in.

In the end I just used to switch stop start off as soon as I started the car.

Seek help from a specialist garage  

So not Skoda then. 

So, ultimately, I didn't realise that the infotainment unit actually told you the reason, that makes it somewhat clearer one I found it.

 

I definitely agree that the messages can be cryptic though, messages such as 'power consumption too high' or 'engine needs to be running' don't really explain the reasoning, lol.