Car problems

[Paul Bradfield 7]

I have a 2011 330i Msport convertible 

New after market generic battery 12 months ago (Century) which was Coded by Midas. Since them every so oftern when car has been parked & I come back to start,  its totally dead no lights nothing works, & always a few hours later its OK. It has been on the diagnostic several times, Battery has been recoded the CPU had been removed & sent in to GET electronics to be tested, no issues. However the problem comes back maybe 3 weeks later & sometimes a few days later. Have spoken with BMW, & they have said because the problem is intermittent its very differcult. to pinpoint. So am at wits end in where to go next.

Dont' know if this is related but sometimes the car runs a little rough on start up, but & if I restart it its usualy OK.

Has anyone had a similar experence with their car  ? Suggestions welcomed 

[F10er 65]

Who has been diagnosing the car and are there any fault codes stored in the car?

[Paul Bradfield 7]

Hi & thank you for your interest. I have included the files that mostly relate top this rather than try & write it all down

 

[promo 93]

Hiya, 

check FRM and JBBF module for potential water ingress which may relate to the no lights etc

Edited February 2, 2022 by promo

[F10er 65]

For the rough running fault i would suspect the injectors. The N53 (which i think your engine will be as it's a UK spec) is notorious for injector issues (especially cold start misfires) and I'm pretty sure there was a recall issued for the injectors in the UK. Can you know if that recall was ever done? 

For the starting issue, it could be a corroded main engine earth cable (known to corrode especially on UK cars) Or the other possibility is where battery cable passes through the body from the battery compartment. There is a connection there that often corrodes if there has been water in the battery compartment. You have to remove the battery to check this which is a bit of a pain on a convertible. 

[Paul Bradfield 7]

The sound of the battery cable corroded is something a friend of mind had also menchioned, I think you have a valid point I will check this. thankyou

[The Bimmer 11]

if your car have comfort access try disconnect the door handle connection or disconnect from control unit or disconnect any aftermarket fitted accessories. 

[Paul Bradfield 7]

No It doesnt have that