BMW diagnostic connector and reading?

[Mikael Nordin]

Hi all,

I have a BMW 525i 24V -92 and I have some questions that maybe someone
of you can help me with. I would like to service my own car but don't
want to by a ~2000 $ tool to be able to read the fault codes.

- I wounder if there is anyone who know where to get the specifications
  for the BMW diagnostic connector?
- What type of interface is used on PIN 15 (RXD) and 20 (TXD)?
  Is it a RS232 or a CAN interface or something else?
- What type of equipement is needed to read the fault codes ?
  Is it possible to read on the display (Check Control) on the dashboard ?
  Or only with a PC connected to Diagnostic connector?
- Where (book, web etc.) can I find the fault code translation and
  Description? Available from BMW, Hayes, Bentely etc.?
- Is it possible to find the interface protocol specification somewhere?

My deepest thanks for all help,

/Micke