BMW diagnostics.

[bl1300]

This is probably a long shot and a half but if anywhere is going to have the anwser its probably here.

I want to read the fault code on my e36 to discover why the SRS light is on and ideally I want to do this tomorrow morning.
I do have a diagnostics scanner, 2 in fact, but I am aware that BMWs of this era don't use the now near enough standard OBDII diagnostics socket and I don't have the right adapter.

I was thinking if I new which pin on the car to connect to which pin of the OBDII reader I could make up an adapter in a few minutes from the endless pile of wiring offcuts in the workshop. That would hopefully allow me to read the code tomorrow rather than waiting for postage on the correct adapter.

[scaryoldcortina]

I'm fairly sure the E36 doesn't use any of the OBD2 protocols, so you won't be able to connect a "universal" scanner at all. I'm also fairly sure that you can connect a LED to one of the pins in the big round socket and count the flashes to read the code instead. I'm just checking exactly how

[scaryoldcortina]

OK, Most but not all E36 models go like this -

Connect a breakout to pin 8 of the ECM, LED between this and battery +
Switch ignition ON
Press accelerator to floor 5 times in 5 seconds
Count flashes - codes come in groups of 4, 0 is 10. End of codes (or no codes) is either 0000 or 1000
Switch ignition OFF remove breakout and LED.


The diagnostic socket is only for dealer spec (or snap-on) code readers, OBD2 ones don't work. I also suspect you won't get an airbag fault with the LED trick - it's powertrain only from looking at the fault code list.

[bl1300]

damn I was hoping the reader would be ok for it as it has the BMW badge printed on the box. I paid quite a bit more to get more langauges and a wider range of suitable vehicles. The reader I have also specifies it will do SRS and ABS codes as well as engine and transmission related codes.

Will try the LED trick or might have to find someone with snap on to read the code.

[adamwatson]

You may be able to bodge it with a bit of lateral thinking if you have a OBDII to USB lead. Download the software here bmwcoders.com/forum/1-post1.html
Here are the pin to pins forums.bimmerforums.com/forum/showthread.php?p=19053287
You'll have to take the BMW socket and the ODB plug part but it should be do-able.

[ejenner]

I have diagnosed one of these using my equipment once before. The system actually works quite well. Surprisingly advanced.

If you can find someone who does BMW diagnostics then they can do it... of course they will charge!

[10mpg]

I have a fairly advanced universal modern OBD2 scanner, and a cheapy Ebay job, and i have an older 'Red brick' Snap on scanner though it is the last of the line full colour graphing red brick so not prehistoric yet..

the Snap on has every available key and most adaptors including the BMW round connector it does full BMW diagnostics, I have tried the proper BMW adaptor with both of the other scanners and it just says no, so i wouldn’t hold out much hope of yours working if you bodged up the connecter to the right pins, the badge on the box almost certainly refers to post '02 OBD2 compliant models..

Another tip is it used to be common for BMW dealers to cut or disconnect one of the wires going into the diagnostic socket, to make sure they came back to the dealer for reading, thus furthering the belief that 'most scanners cant do BMW's'.... worth having a look anyway...

[ejenner]

I did it using my BMW scanning tool. I doubt any modern tool would have the programming, it is very specialist for those earlier cars.

[bortaf]

My blue point reader came with both merc and BMW adapters and reads them, bit more expensive than the £50 universal one i also have, no idea how much it was though i got it in a garage clearance i did.