Start Stop operating conditions.

[RaptorStrike]

Does anyone know what the operating conditions are that are required for start stop to work?

Mine seems to have a mind of its own, especially if the Satnav is on and in Eco Pro mode.

Roundabouts and traffic lights in particular it seems to not work more than it does.

I drove for nearly 2 hrs today and only at one set of lights did it work. The rest it didn't, even in Eco Pro mode.

[740I_yeye]

It depends sometimes, when you put the car in sport it switches it off completely. When you come to a brief stop or have the hold function activated I dont believe it will work. I turn it off most of the time tbh its quite annoying.

[RaptorStrike]

Originally Posted by 740I_yeye

It depends sometimes, when you put the car in sport it switches it off completely. When you come to a brief stop or have the hold function activated I dont believe it will work. I turn it off most of the time tbh its quite annoying.

The auto hold doesn't normally affect it.

Will try it with it off on the way home.

[Al Pinã]

I know cold temperatures affect it. If your heater is on and the car isn't up to full temp then it won't engage.

[RaptorStrike]

Originally Posted by ALPINA_DREAMS

I know cold temperatures affect it. If your heater is on and the car isn't up to full temp then it won't engage.

Car was definitely up to temp. It seems to work better in adaptive and the satnav not on.

Eco Pro and using the satnav and it hardly seems to work. Which seems counterintuitive given it's supposed to be the most economic mode.

[Qsilver7]

Originally Posted by RaptorStrike

Does anyone know what the operating conditions are that are required for start stop to work?

Mine seems to have a mind of its own, especially if the Satnav is on and in Eco Pro mode.

Roundabouts and traffic lights in particular it seems to not work more than it does.

I drove for nearly 2 hrs today and only at one set of lights did it work. The rest it didn't, even in Eco Pro mode.

As long as the car's electrical system can keep all the consumers turned on running...ASS will shut the engine down if the prerequisites listed below apply. If cutting the engine off and keeping all the electrical consumers running will drain the battery beyond the allowable threshold...the engine will not shut off.

There's a list of additional "switch off inhibitors" listed at the link to the TIS below.

Prerequisites for ASS (from the TIS website): https://www.newtis.info/tisv2/a/en/g...ystem/DPSh9bUd

Prerequisites of an automatic engine shutdown

The automatic engine start-stop function will only stop or start the engine if certain prerequisites are met.

Engine shutdown

The engine is switched off when:

• The vehicle is stationary (speed < 0 kmh).
• The engine speed is virtually at idle speed.
• The vehicle has been driven at > 10 km/h since the engine was last shut down.
• The vehicle has been driven at 10 km/h since the last change at terminal 15.
• The brake is pressed.
• Steering wheel movement is not moved. Steering wheel must be aligned straight.

[jettie1767]

Thank God I don't have the start-stop function!

[740I_yeye]

Originally Posted by jettie1767

Thank God I don't have the start-stop function!

Whats in the place where the button would be on your car??

[Qsilver7]

Originally Posted by 740I_yeye

Whats in the place where the button would be on your car??

The Alpina B7's Start/Stop button looks like #2 in the diagram below:

[pugxs]

I didn't realise the auto stop start only kicks in if the steering wheel is in the 'straight' position! Certainly explains why my auto stop doesn't kick in at times I expected it to!!!

[RaptorStrike]

Originally Posted by pugxs

I didn't realise the auto stop start only kicks in if the steering wheel is in the 'straight' position! Certainly explains why my auto stop doesn't kick in at times I expected it to!!!

It doesn't stop it working on mine.

Today I tried a test. I set off from home in adaptive and every roundabout I stopped at, regardless of wheel position, it worked. The first was 2.5miles from my house. I drove for a total of 10 miles. Both front seats heating was on and so was the steering wheel heating as it was 6deg and I have them set to auto come on at 8deg.

I then drove for 2hrs on the motorway (1 hr each way with 2 miles at the end to the place I was going to) sat at 70mph on cruise and in Eco Pro

The last 10 miles of my journey home was the same 10 miles I did first thing this morning.

In Eco Pro it only worked at one roundabout and I think that was because I stopped about 150m short due to traffic.

The only other time it worked was when I reversed onto the drive at home.

So for me anyway the position of the steering wheel doesn't affect it.

I just find it odd that in Eco Pro which is supposedly the cars most economical mode, the start stop doesn't work like it does in adaptive. :

[bigmac f02+g12]

Originally Posted by RaptorStrike

It doesn't stop it working on mine.

Today I tried a test. I set off from home in adaptive and every roundabout I stopped at, regardless of wheel position, it worked. The first was 2.5miles from my house. I drove for a total of 10 miles. Both front seats heating was on and so was the steering wheel heating as it was 6deg and I have them set to auto come on at 8deg.

I then drove for 2hrs on the motorway (1 hr each way with 2 miles at the end to the place I was going to) sat at 70mph on cruise and in Eco Pro

The last 10 miles of my journey home was the same 10 miles I did first thing this morning.

In Eco Pro it only worked at one roundabout and I think that was because I stopped about 150m short due to traffic.

The only other time it worked was when I reversed onto the drive at home.

So for me anyway the position of the steering wheel doesn't affect it.

I just find it odd that in Eco Pro which is supposedly the cars most economical mode, the start stop doesn't work like it does in adaptive. :

When was the last time u charged ur battery ? If battery is low it will not activate or if u have ur heat setting up high and the cabin has not reached that desired temp yet is also will not activate

[jettie1767]

Originally Posted by 740I_yeye

Whats in the place where the button would be on your car??

Still has a plain silver button thingy. Can't press it...it's just there.

[RaptorStrike]

Originally Posted by bigmac f02+g12

When was the last time u charged ur battery ? If battery is low it will not activate or if u have ur heat setting up high and the cabin has not reached that desired temp yet is also will not activate

I charged the battery overnight last night to check that wasn't a reason. On my Mercedes it often would be the battery charge that would be holding it back.

But this morning the car when I set off had a fully charged battery according to my CTEK charger.

I'd be extremely surprised if the 45 mins I spent out of the car before the journey back home depleted the battery so much that it didn't work.

I am confident that isn't the case as the battery was new at beginning of Dec, replaced by BMW. I've checked it with a battery tester and it's health is reading at 100%.

[JustinP]

To find out why the engine is still running when the car is stationary and start/stop is enabled, in the idrive ‘My Vehicle’ menu, click ‘technology in action’ and then ‘efficiency dynamics ’.

The screen reports things like roundabout detected, which presumably is picked up from the sat nav, or comfort requirements which I guess means the car is either cooling or heating the cabin.

[Qsilver7]

Just an FYI in case the link posted in post #6 was utilized/clicked on...along with the "prerequisites" for automatic engine shut down listed in that post...the link to the TIS website gave another long list of switch-off inhibitors":

Switch-off inhibitors

The engine continues running although the vehicle is at standstill and held with the brake pedal.

The following preconditions act as switch-off inhibitors and prevent the engine from shutting down:

• Engine adaptation (e.g. cylinder adjustment)
• Regeneration of the diesel particulate filter
• Carbon canister needs purging
• Insufficient knock resistance of fuel
• Engine fault
• Engine coolant temperature
• below a defined value (depending on engine version approx. 20 ‐ 60 °C)
• above a defined value (depending on engine version approx. 100 ‐ 130 °C)
• Automatic transmission not ready
• Gearbox adaptation active
• Drive position “S”, “M”, “N”, “R”
• Driving surface incline too great
• Assist system active (Active Cruise Control, Parking Assist, Hill Descent Control)
• Stop-and-go driving
• Last MSA stop was too long
• Air conditioning requirements:
• Automatic air conditioning: MAX AC button pressed
• Automatic air conditioning: Defrost button pressed (request to defrost the windscreen)
• Air conditioning system: high blower speed and low blower temperature, compressor button pressed
• Air conditioning system: high blower speed and air distribution directed to windscreen, compressor actuated
• Ambient temperature ≤ 3 °C
• Engine speed > 1200 rpm

• Battery condition:
  • State of charge too low
  • Measured battery state of charge not plausible
  • Battery temperature too high (approx. 50 °C)
  • Starting voltage drop from previous ASSF start too low
• Vehicle rolling

[Moopai]

Does the Stop/Start really save that much in gas? I've always wondered damage is this function causing overtime!

Originally Posted by Qsilver7

Just an FYI in case the link posted in post #6 was clicked...along with the "prerequisites" for automatic engine shut down listed in that post...the link to the TIS website gave another long list of switch-off inhibitors":

Switch-off inhibitors

The engine continues running although the vehicle is at standstill and held with the brake pedal.

The following preconditions act as switch-off inhibitors and prevent the engine from shutting down:

• Engine adaptation (e.g. cylinder adjustment)
• Regeneration of the diesel particulate filter
• Carbon canister needs purging
• Insufficient knock resistance of fuel
• Engine fault
• Engine coolant temperature
• below a defined value (depending on engine version approx. 20 ‐ 60 °C)
• above a defined value (depending on engine version approx. 100 ‐ 130 °C)
• Automatic transmission not ready
• Gearbox adaptation active
• Drive position “S”, “M”, “N”, “R”
• Driving surface incline too great
• Assist system active (Active Cruise Control, Parking Assist, Hill Descent Control)
• Stop-and-go driving
• Last MSA stop was too long
• Air conditioning requirements:
• Automatic air conditioning: MAX AC button pressed
• Automatic air conditioning: Defrost button pressed (request to defrost the windscreen)
• Air conditioning system: high blower speed and low blower temperature, compressor button pressed
• Air conditioning system: high blower speed and air distribution directed to windscreen, compressor actuated
• Ambient temperature ≤ 3 °C
• Engine speed > 1200 rpm

• Battery condition:
  • State of charge too low
  • Measured battery state of charge not plausible
  • Battery temperature too high (approx. 50 °C)
  • Starting voltage drop from previous ASSF start too low
• Vehicle rolling

[RaptorStrike]

After a software update by the dealer today to the version in the picture. The S/S performs way better and even works as I'd expect in Eco Pro mode.