[SpeedTrip]

In this colder weather in Leafy Surrey, after a few days not using the M140i - I fired it up & drove 2 miles ... when shutting down, it produced a Low Battery warning Message



It fired up again an hour later with no apparent effort & I took it for a 15 mile drive on fast roads - again when shut down the Low Battery warning ...



Question - is it safe to charge the Battery in situ, or must it be removed from the Car - seem to recall that there are 'sensitive' electrical components that can be damaged if charged in situ ?


Advice appreciated !

[No one]

Of course you can charge the battery without removing it, provided you have the facility! Removing is troublesome: the battery weighs and it's hard to unlock the boot without the battery installed (I don't know if the jump starting terminals under the hood can be used. The manual, page 35, only suggests reaching from the cabin.).

Here you are (the OEM charger): https://www.realoem.com/bmw/enUS/sho...diagId=03_2939. Just notice the manual, page 263.

From your description you drive too little to even restore the charge that has been used to start. It's overall bad for the battery to keep it low. I recall the last time I had the warning (so bad, the cabin ventilator was disabled, in a very cold winter weather with frosted windows, I could hardly drive ) it took a 200 km drive on a fast road to recharge the battery and have the ventilator enabled again.

[SpeedTrip]

Thanks - I think !

[IJO]

Originally Posted by No one

Of course you can charge the battery without removing it, provided you have the facility! Removing is troublesome: the battery weighs and it's hard to unlock the boot without the battery installed (I don't know if the jump starting terminals under the hood can be used. The manual, page 35, only suggests reaching from the cabin.).

Here you are (the OEM charger): https://www.realoem.com/bmw/enUS/sho...diagId=03_2939. Just notice the manual, page 263.

From your description you drive too little to even restore the charge that has been used to start. It's overall bad for the battery to keep it low. I recall the last time I had the warning (so bad, the cabin ventilator was disabled, in a very cold winter weather with frosted windows, I could hardly drive ) it took a 200 km drive on a fast road to recharge the battery and have the ventilator enabled again.

I agree. leaving the battery at a low state of charge will reduce it's capacity and not driving far enough won't recharge it sufficiently.

Connect a charger to the underbonnet terminals until it indicates fully charged.
Buy a voltmeter that plugs into the in car power socket so you can monitor the battery and charging voltages.

[No one]

Originally Posted by IJO

Buy a voltmeter that plugs into the in car power socket so you can monitor the battery and charging voltages.

There's not much need for that: the hidden menu (https://f20.1addicts.com/forums/showthread.php?t=715852) can be used. Further, are the car's power sockets enabled when the engine is not running (to check the battery rather than the alternator's charging voltage)? I'll check that.

Yet, even when only the ignition is on there's some load on the battery, so Battery Comfort Indicator might make some sense still. According to other videos it should be possible to see the "target" 12+ volts through the menu though. I'll check mine but I need to be sure it's well charged to interpret the value correctly. That is currently an issue.

[No one]

Originally Posted by No one

are the car's power sockets enabled when the engine is not running (to check the battery rather than the alternator's charging voltage)?

Yes they are.