[ctuna]

You are suppose to charge the battery from the charge posts in the Engine Bay.

If you find connectors not plugged in it is usually from options that are not installed.

This is the stereo board you will get better responses and more exposure on the general board.

bmw boards and links
https://www.bimmerfest.com/forums/forumdisplay.php?f=99
https://www.e90post.com/forums/forumdisplay.php?f=27
https://www.e90post.com/forums/forumdisplay.php?f=2
https://www.e90post.com/forums/forumdisplay.php?f=122
https://bimmerretrofit.com/store/
https://www.e90post.com/forums/forumdisplay.php?f=197
https://www.e90post.com/forums/forumdisplay.php?f=378
https://www.e90post.com/forums/forumdisplay.php?f=16
https://www.e90post.com/forums/forumdisplay.php?f=368

It would be a good idea to get BMW Stanadard Tools and Ista D if you are doing DIY's . These are programming and diagnostic programs.

They are original from BMW. You can get the downloads free from the coding sub forum . You also need a K/D can cable and PC laptop.
Ista D is like having a shop manual with guided trouble shooting.

diagnostic manual ista/inpa
https://www.google.com/url?sa=t&rct=...xo19teM9vkTF-C
https://www.google.com/url?sa=t&rct=...7x8H3pN8h1fMuF
https://bimmerprofs.com/diagnostics-inpa-part-1/
https://www.google.com/url?sa=t&rct=...lkXEhlQYy4i9Nb
https://www.bimmerforums.com/forum/s...-P-actually-do
https://www.bimmerfest.com/forums/at...1&d=1590283589
https://www.google.com/url?sa=t&rct=...kBbC27TJLX3BGe
https://www.google.com/url?sa=t&rct=...WekqhcC6hsgK2c
https://www.e90post.com/forums/showthread.php?t=1649066
primary links
https://www.e90post.com/forums/showthread.php?t=1681573
https://www.bimmerfest.com/threads/t...-pdfs.1449540/
ista problems
https://www.e90post.com/forums/showthread.php?t=1661945
https://www.e90post.com/forums/showthread.php?t=1581663
https://www.youtube.com/@BMWDoctor
Diagnostic Manuals Inpa/Ista D
https://bimmerprofs.com/diagnostics-inpa-part-1/
https://www.google.com/url?sa=t&rct=...7x8H3pN8h1fMuF
https://carmod.ru/files/icom/istad_en.pdf
https://www.e90post.com/forums/showthread.php?t=1681573
https://www.bimmerforums.com/forum/s...-P-actually-do
primary links
https://www.bimmerfest.com/forums/at...9&d=1539905743
https://www.e90post.com/forums/showthread.php?t=1681573
https://www.bimmerfest.com/forums/at...1&d=1590283589