[Rowant]

Hello all. I am interested in having a play with a diagnostic program at obd-2.com and so I have downloaded it but I have no idea how the various plugs should be wired (and no indication is given). I have found a diagram showing the industry standard for wiring obd2 to db9 but I am unsure if Land Rover used this or just did it´s own thing - or a combination of both.
I have a 1995 4.6 hse.
Thanks in anticipation

 

[BBS SPY]

Hiya Rowant.

industry standard for wiring obd2 to db9

I am really worried about this statement.
The DB9 is just a connector type, it is often used as the output connector on a variety of vehicle communication interfaces, however the designation of what pin does what in such usage cases is in no way standardized. DB9 is also used most notably for the serial port connector on earlier PC's, however serial ports on PC's should never be connected directly to any pin of an OBDII connector under any circumstances. Doing so has a high chance of damaging your PC. :naughty:

If you want to experiment, i strongly recommend getting and using the ELM323 interface, its cheap, has a lot of software freely available already, a lot of support and documentation and allows for open development and experimentation.
It's never going to give you much access, as most systems on an LR are not OBDII compliant, but it sure won't result in a melted laptop. :thumb:

 

[Rowant]

Gidday BBS

Sorry I missed you reply until now - having a bad day(s).

So there is no industry standardisation of wiring the obd2 to db9 plug. What a bugger!! If that is the case I won´t even attempt to use this program in case I am wasting my time or, even worse, I fry something. I already have a 323 serial to usb adapter.
Let me get this straight - obd2 plug wiring varies with manufacturers and db9 varies also - even with a 323 interface it would most likely end up as just a pile of fertiliser on me. Correct?

Just out of curiosity here is the link to the diagram I was considering using - http://ru.shutorg.com/pdf/OBDII_CABLE.pdf

Cheers

 

[BBS SPY]

Gidday yourself Rowan
Don't sweat it, you have no need to explain, i am as busy as anyone could be myself `)

The OBDII standard does cover which pins are to be used for what signals in some case, none of which are directly compatible with any computers IO port, connector or pins.
However a good number of pins on the OBDII connector are free to be used as the manufacturer wishes, and again, with signals not truly designed to be connected directly to a PC and potentially harmful.

That being said, someone has figured out that you can connect a standard RS232 Port on a PC to the EAS system and there are leads you can buy quite cheaply that are wired like this, as well as open source (commonly referred to as free) software that can be downloaded and used, however as the timing requirement of the EAS is quite specific, there seems to be a lot of trial and error and messing with various timing values to get things working well enough.
Some seem to have no trouble and others end up not being able to do it at all.

The ELM323 interface would give you connectivity to the EMS and possibly the Autobox, but data access, even with provided trial software is quite limited.

Sadly, i believe our own equipment costs a bit more than any light interest level could justify, which is a shame as i would love to show you what the right hardware and software can achieve.

But in the meantime, i hope i have reasonably detailed the situation and saved you from the fertilizer pile as you put it. :roll: