This is not a modern BATTERY service procedure to do on a modern BMW . Using an external power supply is no where mentioned in REP and it will create issues specifically in the OBD , If you do will probably blow the fuse FOR the OBD when you unplug the negative cable and may compromise Ethernet or the gateway also discounting power supply won't cause modern modules to lose memory or any presets that was.older modules from the 90's. ,,BMW doesn't have radio codes or BDC stat release codes like pre E34 models (those older models I do recommend an external power supply) also after this you need a capabe scanner to register battery and able to do scan test, clear faults and initialize systems and almost forgot and if is posibleme do a. Pre scan test to note all faults in modules so you are not liable for modules that got damaged or corrupted by the low voltage supply ( or even go bad during the scan test FRM modules are notorious for this) and also running the ABL energy diagnosis is very important as it may tell you why the battery went dead. Also after battery registration, the vehicle has to go into sleep mode so new voltage is relearn
I use Terminal Anti corrosion washers Fiber. For battery Terminals.
KNOWLEDGEABLE
Thanks 👍
From Nick Ayivor from London England UK 🇬🇧
Thanks for sharing!
This is not a modern BATTERY service procedure to do on a modern BMW . Using an external power supply is no where mentioned in REP and it will create issues specifically in the OBD , If you do will probably blow the fuse FOR the OBD when you unplug the negative cable and may compromise Ethernet or the gateway also discounting power supply won't cause modern modules to lose memory or any presets that was.older modules from the 90's. ,,BMW doesn't have radio codes or BDC stat release codes like pre E34 models (those older models I do recommend an external power supply) also after this you need a capabe scanner to register battery and able to do scan test, clear faults and initialize systems and almost forgot and if is posibleme do a. Pre scan test to note all faults in modules so you are not liable for modules that got damaged or corrupted by the low voltage supply ( or even go bad during the scan test FRM modules are notorious for this) and also running the ABL energy diagnosis is very important as it may tell you why the battery went dead. Also after battery registration, the vehicle has to go into sleep mode so new voltage is relearn
Some good points. Thanks for watching!