BMW Available Interfaces for ODBII

takeda · 04-30-2006, 10:55 AM

Dear friends,

I recently baught an E30 316 M40 BMW. Purpose is to M it, or at least
325 it. Some of the engines i can put in (6 cylinder engines) are

M50B25
* 1991-1995 E36 3-Series
* 1992-1995 E34 5-Series

S50B30US
* 1995 E36 M3

S50B30
* 1992-1995 E36 M3

S50B32
* 1996-1999 E36 M3
* 1997-2000 M Roadster
* 1998-2000 M Coupe

M52B24
* 1995-1999 E36 3-Series
* 2000-2002 E39 5-Series (M52TU)

M52B25
* 1995-2000 E36 3-Series
* 1995-1999 E39 5-Series
* 1997-2001 E46 3-Series (M52T)
* 1998-2001 E39 5-Series (M52TU)
* 1998-2001 E36 Z3 (M52TU)

M52B28
* 1995-2000 E36 3-Series
* 1995-1999 E39 5-Series
* 1995-1999 E38 7-Series
* 1997-1999 E36 Z3
* 1997-2001 E46 3-Series (M52T)
* 1997-2001 E36 Z3 (M52TU)
* 1998-2001 E39 5-Series (M52TU)
* 1998-2001 E38 7-Series (M52TU)

S52B32
* 1996-1999 E36 M3
* 1996-2000 E36 M Roadster/M Coupe

Can you tell which of those can be accessed with ISO OBDII interfaces and through what exaxtly interfaces? ELM, mOByDIC, maybe with andywittaker's (http://www.andywhittaker.com/ecu/obdii_hardware.htm) hardware or only with CARSOFT hardware?

Does anybody has the schematics for the CARSOFT RS232 <--- OBD 1&2 Cable?

It seems really nice with a 200+ hp car to be able to run live data collection programs and because i will install a car pc, i whould like this (live data) option available in my future car (eg, dynamometer). Currently the OBD1 interface the M40 supports does not support livedata

Sorry for my english

Thanks in Advance

petmakris@hotmail.com

PS. Please send any information you have and might concern me, i am looking to unmess things for days

I have search and read most of the previous BMW+OBD threads and i didn't find any spesific and sure to go on with information.
This whould be a change to make a clear and clean BMW+ODB info thread.

takeda · 04-30-2006, 11:01 AM

The available ISO (?) OBD Interfaces are

OBD-II Signal Protocols

There are five protocols in use with the OBD-II interface, and often it is possible to make an educated guess about the protocol in use based on which pins are present on the J1962 connector:

* SAE J1850 PWM (41.6 kbaud, standard of the Ford Motor Company)
o pin 2: Bus-
o pin 10: Bus+
o High voltage is +5V
o Message length is restricted to 12 bytes, including CRC
o Employs a multi-master arbitration scheme called 'Carrier Sense Multiple Access with Non-Destructive Arbitration' (CSMA/NDA)
* SAE J1850 VPW (Variable Pulse Width) (10.4/41.6 kbaud, standard of General Motors)
o pin 2: Bus+
o Bus idles low
o High voltage is +7V
o Decision point is +3.5V
o Message length is restricted to 12 bytes, including CRC
o Employs CSMA/NDA
* ISO 9141-2. This protocol has a data rate of 10.4 kbaud, and is similar to RS-232. ISO 9141-2 is primarily used in Chrysler, European, and Asian vehicles.
o pin 7: K-line
o pin 15: L-line (optional)
o UART signaling (though not RS-232 voltage levels)
o K-line idles high
o High voltage is Vbatt
o Message length is restricted to 12 bytes, including CRC
* ISO 14230 KWP2000 (Keyword Protocol 2000)
o pin 7: K-line
o pin 15: L-line (optional)
o Physical layer identical to ISO 9141-2
o Data rate 1.2 to 10.4 kbaud
o Message may contain up to 255 bytes in the data field
* ISO 15765 CAN (250kbit/sec or 500kbit/sec)
o pin 6: CAN High
o pin 14: CAN Low

Note that pins 4 (battery ground) and 16 (battery positive) are present in all configurations. Also, ISO 9141 and ISO 14230 use the same pinout, thus you cannot distinguish between the two simply by examining the connector.

I think BMW does not use can at all.

Can you tell, the ELM based cables like

http://www.mp3car.com/vbulletin/show...734#post200734

which of those interfaces implement?

Two programs that look nice for livedata analysis are the Dyno-Scan and DigiMoto

1. Are any of them compatible with the above BMW Engines/Cars (I mean purchasing the kit DynoScan/DigiMoto without DIY kits)
2. Is there any schematics or info for the hardware used by either of them?

takeda · 04-30-2006, 11:08 AM

and some photos

takeda · 04-30-2006, 12:06 PM

Nology's information PDF includes a matrix (http://www.nology.com/pdfandzipfiles...rlocations.pdf) but there is no more info available.

takeda · 04-30-2006, 12:29 PM

The interpreter chip

The ELM323 was specifically
designed as a low-cost solution for
interfacing a PC or PDA to a vehicle
diagnostics connector. To keep things
simple it communicates at a fixed
baud rate of 9600 baud and does not
offer a handshaking option for the
RS232 interface. In addition it is only
able to communicate using the
10.4 kHz ISO 9141 Protocol. This standard
is the most common used by the
majority of European and Asian manufacturers.
Vehicles built in the US
use VPW and PWM protocols and
suitable interpreter chips are also
available from Elm Electronics.

G. Müller

so remaining questions are

1. Are the BMW 6cyl engines compatible with the ELM323 based OBD2 scanners? or which protocol does BMW use?

SAE J1850 PWM
SAE J1850 VPW
ISO 9141-2.(RS-232)
ISO 14230 KWP2000 (Keyword Protocol 2000)
ISO 15765 CAN

??

2. Is Dyno-Scan (xor DigiMoto) compatible with the ELM323 based RS232 scanner cables?

3. (NEW!) are BMW ecu information ISO defined? can I perfom a dynamometrisis with Dyno-Scan to a BMW?

takeda · 04-30-2006, 02:01 PM

I am really happy that i am answering my self. Although i am waiting for an expert here...

thus, from the FAQ in this section i read

There are three basic OBD-II protocols in use, each with minor variations on the communication pattern between the on-board diagnostic computer and the scanner console or tool. While there have been some manufacturer changes between protocols in the past few years, as a rule of thumb, Chrysler products and all European and most Asian imports use ISO 9141 circuitry. GM cars and light trucks use SAE J1850 VPW (Variable Pulse Width Modulation), and Fords use SAE J1850 PWM (Pulse Width Modulation) communication patterns.

Is the bold typed a fact? if so BMW uses RSR232, ISO9141 circuitry.

Sorry for posting and reposting i am about to pick up an engines and mechanical parts, and i want to proceed with caution to the correct choise................................

thanks again

shoulders · 04-30-2006, 02:47 PM

I have been messing with obdII and what i found is BMWs with the obdii socket inside definately have obdII and up until about 2000 - 2002 they used the ISO 9141 protocol (elm 323 will work with these), but newer BMWs are now using the CAN protocol.(you need elm 327 which supports all protocols)

For those BMWs that do not have the OBDii socket in the cabin they might still be obdII compatable. must be at least 1996 onwards, this is when it was made law in america so some european models might be compatable (mine is, 1997 318is coupe M44 engine, motronics ECU)(made law 2002 in europe to be compliant).

the way I checked it is to see if pin 17 is populated in the 20 pin DLC of the BMW connector(second K line), I believe it was a legal requirement to have a seperate line from the ECU to supply OBDII data. Diagrams lable this as TX II or a K line. Also check pin 2 this is sometimes label as OBDII line.

BMW call their diagnostic link the K line as well.

Where the 20 pin dlc has to be used with the ELM interphase you can buy a DB9 (serial type) plug to BMW 20 Pin DLC on EBAY.

Also i think a rule of thumb is later bosche motronic ECUs were compliant but the siemens ones were not ever.

All BMWs can be accessed by carsoft or BMW DIS (dealer software) but as you know only OBDii compliant ones accessed by OBDII interphase and software.

I have diagrams of the carsoft interphase and obdII cables if they are of any help.

As far as i know BMW do use a iso 9141 protocol to communicate to their own stuff but it is slightly different, i.e. the packets are slightly bigger so you can not use an OBDII interphase to get at BMW only stuff i.e. reprogramming the ECU or putting the windows up.

takeda · 04-30-2006, 04:53 PM

Really thanks. Your information rocks. I am really interested in the carsoft hardware schematics and any other information you may have about this.

So as i posted in another thread some more information when the BMW car has no OBD2 fuse but supports it.

If I was you:

1. I whould try before bying the cable to do the following diy stuff. It's plain easy and you need at most 50 cm cable and a cutting tool.

2. I couldn't sleep before getting that thing to work

(don't hang on me , is just what i whould do)

-------------

BMW Diagnosis Socket Pinout for ODB2

14 Battery power
15 ISO 9141-2 L Line
17 ISO 9141-2 K Line
19 GND
20 ISO 9141-2 K Line

OBD2 Diagnosis Socket Pinout

OBDII ------------------ BMW

4,5 ------------------ 19(Ground)
7 ------------------ 17,20(K Line)
15 ------------------ 15(L Line)
16 ------------------ 14(Power)

Yet i don't have latter 96 BMW (and before CAN BUS) to test if this working. If so please write it down here.

So things are getting straight now.

1. hances are models latter 96 to support OBD2 either through the 20 pin diagnostic socket (see above) [if there is no J1962] either through preinstalled OBD2 (J1692) socket.

2. OBD2 Protocols. If the car is 96 latter but 2002 pre, is uses the ISO 9141-2 [ELM, RS232], if later than 2002 uses ISO 15765 CAN

takeda · 05-01-2006, 02:41 PM

shoulders you have pm

teo256 · 05-05-2006, 06:07 AM

Quote: Originally Posted by takeda

Really thanks. Your information rocks. I am really interested in the carsoft hardware schematics and any other information you may have about this.

So as i posted in another thread some more information when the BMW car has no OBD2 fuse but supports it.

If I was you:

1. I whould try before bying the cable to do the following diy stuff. It's plain easy and you need at most 50 cm cable and a cutting tool.

2. I couldn't sleep before getting that thing to work

(don't hang on me , is just what i whould do)

-------------

BMW Diagnosis Socket Pinout for ODB2

14 Battery power
15 ISO 9141-2 L Line
17 ISO 9141-2 K Line
19 GND
20 ISO 9141-2 K Line

OBD2 Diagnosis Socket Pinout

OBDII ------------------ BMW

4,5 ------------------ 19(Ground)
7 ------------------ 17,20(K Line)
15 ------------------ 15(L Line)
16 ------------------ 14(Power)

Yet i don't have latter 96 BMW (and before CAN BUS) to test if this working. If so please write it down here.

So things are getting straight now.

1. hances are models latter 96 to support OBD2 either through the 20 pin diagnostic socket (see above) [if there is no J1962] either through preinstalled OBD2 (J1692) socket.

2. OBD2 Protocols. If the car is 96 latter but 2002 pre, is uses the ISO 9141-2 [ELM, RS232], if later than 2002 uses ISO 15765 CAN

can you explain me better this post? I've a BMW E36 318is 1995 (end of the year).
How can i check if have the ODB II system??

Thanks, Matteo

takeda · 05-05-2006, 09:49 AM

I don't really know..

You could try to find the OBD2 socket somewhere close the drivers seet. If you don't find it, you could ask an expert like in a BMW garage or try to find you car manuals including wirings and circuitry. There are good posibilities for ISO9141-2 OBD2 support through the BMW diagnose socket ofyour car

teo256 · 05-05-2006, 06:12 PM

Quote: Originally Posted by takeda

I don't really know..

You could try to find the OBD2 socket somewhere close the drivers seet. If you don't find it, you could ask an expert like in a BMW garage or try to find you car manuals including wirings and circuitry. There are good posibilities for ISO9141-2 OBD2 support through the BMW diagnose socket ofyour car

How can I recognize the OBD2 socket? If I have it, can you give me some links about cables and software? I'd like to link it with RoadRunner

takeda · 05-06-2006, 02:30 AM

yes, sure

-- OBDII & OBDI Diagnosis

--- Information

http://en.wikipedia.org/wiki/OBD-II
http://www.mp3car.com/vbulletin/arch...p/t-18659.html
http://www.etools.org/files/public/B...ev_2-25-02.htm

http://obdloggers.com/
http://www.andywhittaker.com/ecu/ecu_software.htm
http://www.andywhittaker.com/ecu/obdii_hardware.htm
http://www.auterraweb.com/dyforwi.html
http://www.scantool.ca/
http://www.planetfall.com/~jeff/obdii/
http://www.blafusel.de/misc/obd2mobydic.html
http://www.digimoto.com/
http://www.opendiag.org/
http://www.elmelectronics.com/
http://www.ecplaza.net/eccatalog/lis...words=obd2+can
http://www.wgsoft.de/
http://www.obd-codes.com/
http://carsoft.en.ecplaza.net/17.asp
http://www.obd-technologies.com/
http://scantool.imechatronics.com/obdcable_type_b.htm

http://www.mp3car.com/vbulletin/showthread.php?t=51842
http://www.mp3car.com/vbulletin/arch...p/t-24739.html
http://www.mp3car.com/vbulletin/show...734#post200734

http://www.scantool.net/documents.html
http://www.scantool.net/schematics.html

takeda · 05-06-2006, 02:31 AM

remember another thing the OBD2, another the OBD1. spend some time reading those pages you will understand everything.

Tippa · 05-16-2006, 11:32 PM

So, has enyone tested ODB2 scanner with BMW?

Does it really work?
What software was used?