Hi there, I wonder if anyone is able to help and provide advice. I bought a 2005/05 BMW 530d M-Sport at the weekend that is in great condition, with full service history and all of the paperwork. It drives like a dream.

As I was driving it home from where I bought it, and sitting in heavy London traffic, the i-drive popped up suddenly to say "central electronics failure - you are unable to continue your journey. Please contact BMW" (or words to that effect). Not knowing quite what to do as I was sitting at a red light, the message then vanished and I continued my journey. There didn't appear to be anything untoward with the car. I checked the i-drive diagnostics and it had no errors whatsoever. That message has not appeared since.

On Sunday morning, when the car was cold, I started it up and it was very sluggish to get going. Once it fired up, it was absolutely fine. However, I noticed a message on the i-drive system stating "high rate of battery discharge". We drove to Winchester for the day and the car was absolutely fine, once again. We parked up all day, it started fine at the end of the day and drove home.

I next used the car on Tuesday, but when I went to start it, it just turned over and over. I kept trying but nothing fired, and the battery then went dead. I called out the RAC who did all of their checks. The battery was changed in October 2012 with the correct battery, as verified by Euro Car Parts. The battery condition was fine - holding charge, charging fine, etc. There is no issue with the alternator. When he jumped the car off his van, it fired straight up, but was still a bit sluggish to get going. There was a small puff of smoke from the engine as it started, which I am assuming is unusual.

Once running, there were no error messages at all on the i-drive. The RAC chap suggested a local, independent BMW specialist who could help find the fault with the car. Clearly there was a history of starting problems as the battery terminals had marks on them where it has previously been jump started. I followed the RAC to the garage. The RAC chap (who was brilliant, I might add) went through all of the diagnostics with the chap at the garage, and I agreed to leave my car with them.

The garage got around to looking at the car this morning and they have called me to say that they ran all of the diagnostics and the starter motor is the likely cause. They are unable to do any further diagnostics until the starter motor is replaced, which I have authorised.

I am not technically minded at all, but would anyone else in the know with these cars know if the starter motor could send these messages of electronic failure and high rates of battery discharge to the i-drive?

Both the garage and RAC have been very helpful so far, but I just have this inner fear that I'm paying to have the starter motor replaced (which it probably needs to be anyway, as it is sluggish on turn over) but there may still be an underlying electrical fault with the car that might need resolving.

Any other similar stories or solutions would be greatly appreciated!

Thanks.