bmx 1 stop start fault

Cazflin · 11-14-2023, 10:26 AM

My BMW X1 is a 2013, 2L diesel sport. 68,000 on the clock. Had the battery checked and it’s good and fully charged. when I pull up, the stop start is not working. it comes up with stop start failure warning on the screen. Is there a reset button or a stop start motor we could replace. if we disable the stop start button ,when we restart the engine the warning comes back on. no running problems with the car at all. for the last couple of years since I retired We’ve only done 2000 a year. Hoping to change it for an automatic in the next few weeks. any ideas please.

Allworth · 11-15-2023, 11:56 PM

There is no such thing as stop start motor. Starter motor is used to start a car regardless if button is being pushed physically or it is being used by start/stop system. Normally when battery charge is low, start/stop is suspended without any warning, if voltage goes drastically low it will give a warning on battery voltage, so I agree it has nothing to do with a battery. Then; ambient temperature must be above 3C, engine coolant above 60C, vehicle not reversed before stopping, driver seatbelt fastened, vehicle speed - 0 km/h. There are many sensors...

I would have started with a computer diagnostic to track an issue.
I do always carry $40 diagnostic tool that of a size of a matches box and connects to a smartphone this works with all BMWs.

RXeckless · 11-16-2023, 06:00 AM

Quote:

Originally Posted by Cazflin

My BMW X1 is a 2013, 2L diesel sport. 68,000 on the clock. Had the battery checked and it’s good and fully charged. when I pull up, the stop start is not working. it comes up with stop start failure warning on the screen. Is there a reset button or a stop start motor we could replace. if we disable the stop start button ,when we restart the engine the warning comes back on. no running problems with the car at all. for the last couple of years since I retired We’ve only done 2000 a year. Hoping to change it for an automatic in the next few weeks. any ideas please.

Sounds like the same issue as mine. Just started recently too.
https://e84.xbimmers.com/forums/show....php?t=2062004

Cazflin · 11-16-2023, 09:53 AM

i did wonder whether an auto electrician could diagnose the problem. we have a basic diagnostic tool so ill give it a try.

Cazflin · 11-19-2023, 03:55 AM

only code was 4AFA. looks like it might be brake vacuum sensor so hopefully not to difficult to sort

Allworth · 11-19-2023, 04:51 AM

Quote:

Originally Posted by Cazflin

only code was 4AFA. looks like it might be brake vacuum sensor so hopefully not to difficult to sort

Haven't done it myself, here is a video on how to change it. Engine compartment of that 3 series looks very similar to x1 with a 2.0 diesel engine.
Also it might be worth trying to clean the code to see if it comes back before judging whether the sensor is bad.
link to video

maxwmiller · 11-27-2023, 12:17 PM

The E90 guys seem to also have this issue, fixed it pretty easily by replacing the sensor. Looks like the part is is nearly every BMW from 2009-current. https://www.e90post.com/forums/showt...acuum%20sensor.

RealOEM shows the part is #34336875605. If you want to cheap out, knockoff or used sensors are available on eBay and other sites, but there is no guarantee of them being useful. Best bet is get the OEM sensor and have assurance the issue will be fixed.

Also, the start/stop function of the car can be disabled for several reasons.
(https://batteryworld.varta-automotiv...-does-not-work)

11-14-2023, 10:26 AM	#1
Cazflin Registered 0 Rep 3 Posts Drives: bmw x1 Join Date: Nov 2023 Location: uk iTrader: (0)	bmx 1 stop start fault My BMW X1 is a 2013, 2L diesel sport. 68,000 on the clock. Had the battery checked and it’s good and fully charged. when I pull up, the stop start is not working. it comes up with stop start failure warning on the screen. Is there a reset button or a stop start motor we could replace. if we disable the stop start button ,when we restart the engine the warning comes back on. no running problems with the car at all. for the last couple of years since I retired We’ve only done 2000 a year. Hoping to change it for an automatic in the next few weeks. any ideas please.
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11-15-2023, 11:56 PM	#2
Allworth First Lieutenant 204 Rep 383 Posts Drives: X1 xDrive20d (E84) Join Date: Jul 2021 Location: Stoke-on-Trent iTrader: (0)	There is no such thing as stop start motor. Starter motor is used to start a car regardless if button is being pushed physically or it is being used by start/stop system. Normally when battery charge is low, start/stop is suspended without any warning, if voltage goes drastically low it will give a warning on battery voltage, so I agree it has nothing to do with a battery. Then; ambient temperature must be above 3C, engine coolant above 60C, vehicle not reversed before stopping, driver seatbelt fastened, vehicle speed - 0 km/h. There are many sensors... I would have started with a computer diagnostic to track an issue. I do always carry $40 diagnostic tool that of a size of a matches box and connects to a smartphone this works with all BMWs. __________________ 1995 E34 525td auto • 2016 F30 320ed auto
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11-16-2023, 09:53 AM	#4
Cazflin Registered 0 Rep 3 Posts Drives: bmw x1 Join Date: Nov 2023 Location: uk iTrader: (0)	i did wonder whether an auto electrician could diagnose the problem. we have a basic diagnostic tool so ill give it a try.
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11-19-2023, 03:55 AM	#5
Cazflin Registered 0 Rep 3 Posts Drives: bmw x1 Join Date: Nov 2023 Location: uk iTrader: (0)	only code was 4AFA. looks like it might be brake vacuum sensor so hopefully not to difficult to sort
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11-27-2023, 12:17 PM	#7
maxwmiller Private 8 Rep 63 Posts Drives: 2013 X1 xDrive2.8i Join Date: Dec 2022 Location: CA iTrader: (0)	The E90 guys seem to also have this issue, fixed it pretty easily by replacing the sensor. Looks like the part is is nearly every BMW from 2009-current. https://www.e90post.com/forums/showt...acuum%20sensor. RealOEM shows the part is #34336875605. If you want to cheap out, knockoff or used sensors are available on eBay and other sites, but there is no guarantee of them being useful. Best bet is get the OEM sensor and have assurance the issue will be fixed. Also, the start/stop function of the car can be disabled for several reasons. (https://batteryworld.varta-automotiv...-does-not-work)
	Appreciate 0 Quote