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. 

 

 

 

Hi David

Welcome to the Forum

First is the battery actually correct for the car (ie same as the original) ? If it isn't that is not helping

Check the live terminal and all it's connections particularly the small single wire (battery condition sensor). When a battery is not registered to the chassis it may not charge correctly, if it is an exact replacement sometimes you are OK. Not very often though

If you are lucky disconnect the battery (make sure it is correct type and rating for your car) make sure it is fully charged leave the battery disconnected for at least 30min then reconnect. That should reset everything

To be certain there is no damage you need a diagnostic check so if you don't have the equipment you will need the help of a mechanic/garage who has you could also get them to register the battery

Dave

On 10/29/2023 at 4:12 PM, Greydog said:

Hi David

Welcome to the Forum

First is the battery actually correct for the car (ie same as the original) ? If it isn't that is not helping

Check the live terminal and all it's connections particularly the small single wire (battery condition sensor). When a battery is not registered to the chassis it may not charge correctly, if it is an exact replacement sometimes you are OK. Not very often though

If you are lucky disconnect the battery (make sure it is correct type and rating for your car) make sure it is fully charged leave the battery disconnected for at least 30min then reconnect. That should reset everything

To be certain there is no damage you need a diagnostic check so if you don't have the equipment you will need the help of a mechanic/garage who has you could also get them to register the battery

Dave

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.

You need diagnostics, incorrect battery charging can cause over charging and damage to the Alternator as well as control units

The beeping could well be the alarm which has an internal battery though I have not come across this before. A healthy battery will show 12.5 to 12.8v  when charging around 14 to 14.2v

Have you checked all the fuses

Dave