[Jimmy-M2OG]

Hi, only had my car a month but have noticed the stop/start function has stopped working, car is up to temp etc, I checked the voltage of the battery on the cars hidden menu and with the engine running the gauge is showing 13.6V's (my wee one series shows 14.2V's with engine running) and drops to 12v when I switch engine off. Car has AUC bmw warranty and to be honest I will be getting the function coded out but it annoys me that there's a possible problem with the car.

Cheers in advance

[F30Andy]

I take it that ASS worked at one stage then?

Although it would bug me that there is a potential issue with the car, it's one I could live with (had I not already coded it permanently off ) until the car goes in for the next service.

[teaston]

This would be a bonus imo!

[225]

Originally Posted by teaston

This would be a bonus imo!

Agreed! However if there is a fault somewhere best get it fixed the code it off.

[Anton_555]

My auto stop-start stopped working recently, no errors or warning, just permanently said not available. Turned out to be because my air con needed re-gassing. I'm assuming that because the air con was so inefficient, it was driving the compressor extra hard and that's probably one of the sensors for enabling stop-start. Might not be your issue but worth a look. If I turned off the air con using the button once everything was up to temperature, the stop-start function returned..... then turning the air-con back on instantly inhibited stop-start at all times.

[evdok]

ASS not working for some reason, temp was warm & outside was 4.5, could it be the battery on the way out?

ignition on/off

[aquazi]

How old is the car/ battery?

On my old A5 and the wifes Qashqai.... this happened due to the battery..... one of the symptoms (along with keyless being intermittent)

[999rigger]

13.6 volts is not enough to charge the battery fully. Either battery or alternator is faulty i would say.

[stu14t]

There are numerous vehicle parameters that are monitored as a part of the stop/start function to ensure the driving experience is not impacted. As many of the factors are not possible to monitor it may appear that the feature is not working.

Reasons why the stop/start may not shut down the engine include:

• The car is coasting (manual transmission)
• Brake vacuum reading is too low (manual transmission)
• Insufficient brake pedal pressure is being applied to hold the vehicle stationary (automatic transmission)
• Stopping on a hill/downhill with a 12% or greater gradient
• If the steering angle is more then 6 degrees
• If the steering wheel is being moved after approximately one second of coming to a stop
• The system has not yet be activated by going over a speed of 5mph for automatics, 3mph for manuals since the last engine switch off
• If the accelerator pedal is being pressed (engine must be at idle speed only)
• You're coming to a stop from reverse
• The driver gets out of the car
• If Hill Decent Control (HDC) is activated
• If the engine is not up to temperature
• If the DPF is being purged
• Poor quality fuel detected
• Transmission adaptation is active (automatic transmission)
• The hydraulic pressure accumulator is not yet up to pressure (automatic transmission)
• Stop-and-go traffic - system is only activated by driving over 5mph for automatics, 3mph for manuals
• Battery charge is low
• Outside temperature is colder then 3 deg/C
• Outside temperature above 35 deg/C and the air conditioning system is on
• Fogging of the windscreen is detected by the IHKA system
• Climate control system is on but passenger compartment has not yet reached desired temperature
• ABS system was used when coming to a stop

[PX3]

I had this issue on my old E90 and it turned out to be a fuel sensor. As stu has pointed out, there are so many possibilities.

[evdok]

The only thing I can think of is i had to use Morrisons fuel the other day, first time on supermarket fuel or the battery is starting to play up, car is 4.3 years old & does around 5k a year, currently on 26k.

(Fogging of the windscreen).... Windscreen is filthy inside ill clean today & see what happens.

ps: & show off my new rear lights...love them.

[Iyrix]

I find that if i've got my heated seat on, (which is on most of the time in the weather) the SS is less frequent. I didn't have it on this morning and over a 1 hour journey in lots of traffic it was on/off all the time...

[juanmolano]

Originally Posted by stu14t

There are numerous vehicle parameters that are monitored as a part of the stop/start function to ensure the driving experience is not impacted. As many of the factors are not possible to monitor it may appear that the feature is not working.

Reasons why the stop/start may not shut down the engine include:

• The car is coasting (manual transmission)
• Brake vacuum reading is too low (manual transmission)
• Insufficient brake pedal pressure is being applied to hold the vehicle stationary (automatic transmission)
• Stopping on a hill/downhill with a 12% or greater gradient
• If the steering angle is more then 6 degrees
• If the steering wheel is being moved after approximately one second of coming to a stop
• The system has not yet be activated by going over a speed of 5mph for automatics, 3mph for manuals since the last engine switch off
• If the accelerator pedal is being pressed (engine must be at idle speed only)
• You're coming to a stop from reverse
• The driver gets out of the car
• If Hill Decent Control (HDC) is activated
• If the engine is not up to temperature
• If the DPF is being purged
• Poor quality fuel detected
• Transmission adaptation is active (automatic transmission)
• The hydraulic pressure accumulator is not yet up to pressure (automatic transmission)
• Stop-and-go traffic - system is only activated by driving over 5mph for automatics, 3mph for manuals
• Battery charge is low
• Outside temperature is colder then 3 deg/C
• Outside temperature above 35 deg/C and the air conditioning system is on
• Fogging of the windscreen is detected by the IHKA system
• Climate control system is on but passenger compartment has not yet reached desired temperature
• ABS system was used when coming to a stop

Hi, do you know if after resetting the automatic transmission adaptations with Carly, it is posible that the start-stop is disabled? The car is a F22 220i 2016.

[JimTyler]

I use my car once a week on average for about an hours drive and stop start pretty much only works if I dont use any other electrics.
failing that I need to do a few more trips to fully charge it.

[HighlandPete]

Originally Posted by JimTyler

I use my car once a week on average for about an hours drive and stop start pretty much only works if I dont use any other electrics.
failing that I need to do a few more trips to fully charge it.

Problem is with our cars, driving more miles doesn't necessarily mean the SOC (State of Charge) improves very much. Capacity is left for the harvest of energy on the over-run. So it is more the type of driving, than miles themselves, which can add to a SOC above 75 - 80%.

May be worth an occasional charge with a smart charger, particularly in winter. Ensure you have a bit of extra battery capacity for running the higher energy consumers.

[greatbm]

Originally Posted by HighlandPete

Problem is with our cars, driving more miles doesn't necessarily mean the SOC (State of Charge) improves very much. Capacity is left for the harvest of energy on the over-run. So it is more the type of driving, than miles themselves, which can add to a SOC above 75 - 80%.

May be worth an occasional charge with a smart charger, particularly in winter. Ensure you have a bit of extra battery capacity for running the higher energy consumers.

I have ran BMW's for a good number of years and have always carried out the occasional battery charge through winter months to maintain the battery with no problem with start stop.

[janea1207]

Hi guys! Who can tell how to disable(FDL coding) not working start/stop when less outside than 3°. Want working start/stop also when outside is cold

[robbiep]

Originally Posted by janea1207

Hi guys! Who can tell how to disable(FDL coding) not working start/stop when less outside than 3°. Want working start/stop also when outside is cold

Bad idea. At low temperatures, batteries don't work as well. That is why it is disabled, to lessen the chance of repeated stop/starts in traffic at very low temperatures from trashing the battery.

[t5pilot]

Originally Posted by Jimmy-320msport

Hi, only had my car a month but have noticed the stop/start function has stopped working, car is up to temp etc, I checked the voltage of the battery on the cars hidden menu and with the engine running the gauge is showing 13.6V's (my wee one series shows 14.2V's with engine running) and drops to 12v when I switch engine off. Car has AUC bmw warranty and to be honest I will be getting the function coded out but it annoys me that there's a possible problem with the car.

Cheers in advance

Lot's of responses above for you mate. Bottom line is, it should work. With a low mileage car, I'd really suspect it's down to the battery. Use the warranty, get it in & sorted. Although it's more than likely battery health-related, there's always the chance there could be some other underlying issues.
Don't take any chances, especially as the weather conditions are likely going to worsen over the next few months. That's what the warranty's for

[robbiep]

Originally Posted by t5pilot

Lot's of responses above for you mate. Bottom line is, it should work. With a low mileage car, I'd really suspect it's down to the battery. Use the warranty, get it in & sorted. Although it's more than likely battery health-related, there's always the chance there could be some other underlying issues.
Don't take any chances, especially as the weather conditions are likely going to worsen over the next few months. That's what the warranty's for

Jimmy's original post is over 2 years old

[t5pilot]

Originally Posted by robbiep

Jimmy's original post is over 2 years old

I should probs pay more attention!

[janea1207]

Originally Posted by robbiep

Bad idea. At low temperatures, batteries don't work as well. That is why it is disabled, to lessen the chance of repeated stop/starts in traffic at very low temperatures from trashing the battery.

I know but I mean when outside is 0° and the battery is new. Today stay 2 hours in traffic with working engine (0° was outside).
Who knows how to disable this option thru FDL coding???( do not swich of start/stop when outside is cold)
Thanks