bongodave

Thanks for reply. Battery, initially wasn't the right one (non AGM or stop start) but worked for about a week fine. Want until got to it one day and all was dead, no dash, no signs life or central locking but lights work. Disconnected battery and beeping noise which wasn't there before. Changed for correct, AGM stop start battery now and left disconnected overnight. Still dead. Al terminals are tight and the little wore you talk of is connected to pos terminal fine. 12v is getting to alternator constant feed and starter relay seems ok. Still beeps when battery disconnected for a few mins. Really odd one.

Pretty much as the title says really. Replaced the battery and didn't know about coding. Car worked for maybe 50miles or so then went to it one day and totally dead. No dash display, no central locking but electrics are there somewhere as the window still works when door closes. Really panicking that I've buggered up something major. Despite this monumental !Removed! up I am relatively car savvy so don't worry about using language you think reflects my mentality after this mistake lol. It's a 2016 f21 118i. Any pointers would be greatly appreciated.