Ducato Where do I start looking?

[mprowe]

Hi,

Can anyone tell me where the centre of excellence lies within this forum, so I can find information and advice in the OBD domain?
As I am not sure of the terminology or the relevant TLA's (three letter acronyms), the forum search is not throwing up any real help. It seems that maybe OBD deserves a Zone to itself?

To be more specific, I am trying to probe my Ducato based motorhome for status information. Such as door open/close, gear selection and handbrake position.

Assumptions made so far are, there are two protocols in use in my Ducato: ISO 14230 or KWP2000 and CAN.

How am I doing so far?

Best regards, Martin

 

[whine0]

Hi Martin your doing great with a lovely introduction to the forum ,please tell us what year Ducato and motorhome you drive why you want to look at these parameters have you got some diagnostic software to use ? You need to communicate with the body computer for door and hand brake info if yours is 250 or 290 ,gear change is in engine ecu

 

[mprowe]

... please tell us what year Ducato and motorhome <...> have you got some diagnostic software to use?

The Motorhome is a 100 MultiJet (x250?) first registered in 2011. My diag tool is an OBDLink SX (hacked to make an RS232 Sniffer).

If I may report on my findings so far to avoid wasting your time covering the ground already travelled?

If I look at the start of a Body computer conversation (see attached), I see this conversation between a PC & the vehicle.

I think I am fairly happy with the "AT" command, thanks to the ELM327 datasheet. However, I do have two questions at this stage (but many more to follow!):

1. If "7C0" is the CAN address of the body computer, what are the address of any/all of the other nodes in this vehicle?
2. How/where do I find an explanation of the OBD message "4021081" and its valid/error response from this node? Can I request a list of valid commands from a CAN node (a sort of "What can you tell me about yourself" type command)?

With answers to the above, I can (hopefully) ask each CAN node to tell me what they know and thus "suck-out" all the information they contain

Regards, Martin

 

[RS3100]

The Motorhome is a 100 MultiJet (x250?) first registered in 2011. My diag tool is an OBDLink SX (hacked to make an RS232 Sniffer).

If I may report on my findings so far to avoid wasting your time covering the ground already travelled?

If I look at the start of a Body computer conversation (see attached), I see this conversation between a PC & the vehicle.

I think I am fairly happy with the "AT" command, thanks to the ELM327 datasheet. However, I do have two questions at this stage (but many more to follow!):

1. If "7C0" is the CAN address of the body computer, what are the address of any/all of the other nodes in this vehicle?
2. How/where do I find an explanation of the OBD message "4021081" and its valid/error response from this node? Can I request a list of valid commands from a CAN node (a sort of "What can you tell me about yourself" type command)?

With answers to the above, I can (hopefully) ask each CAN node to tell me what they know and thus "suck-out" all the information they contain

Regards, Martin

Why don't you get a copy of MultiEcuScan or FiCom. They will tell you everything you want to know from the ECUs. Or is the journey more important than the destination to you

 

[mprowe]

... Or is the journey more important than the destination to you

You've got it!

But that is not the whole story. I have an In Car Entertainment (ICE) system that is currently hacked into the physical wires. And I know there is a MUCH more sophisticated way to do the same thing.

I could just copy what MultiECUscan do but that takes up too much memory in my Arduino CPU. I need, no, I would like, to understand what I am doing and why.

There must be members within this forum that have trodden this route before. I would like to stand on their shoulders - to paraphrase a very clever person from history!

Regards, Martin

 

[whine0]

That pdf just tells you about the elm and machine your using it’s not telling you anything about the vehicle advise you try different diagnostic system