OBD II interface modification

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boa279
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OBD II interface modification

Post by boa279 »

Just want to gather some opinions from the experts here. Ive been thinking of a project which involves OBD II live data and a PIC. How hard would it be to modify an OBD II kit like this one: http://obddiag.net/index.html

to output live data to a PIC? I know this reader is made with PIC's and outputs the data to a PC with USB. For example, rather than output the data to software on a PC for coolant temp Id like to be able to use the live data to control LED's or an LCD with a PIC through flowcode.

Is this to far fetched or is it possible? Any information would be helpful!

THANKS!

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Steve
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Re: OBD II interface modification

Post by Steve »

It's certainly possible, but you would need to rewrite the firmware in the chip. You might get lucky and be able to get access to the source code and modify that - otherwise, you'd need to start from scratch and that could be a very big development.

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Re: OBD II interface modification

Post by Benj »

Hello

If you can find the CAN message specs for your car and you only want to pull out a couple of values eg coolent temp then it might not be too bad of a job. However if you are trying to make an all encompasing tool that will work on any car then this will indeed be a large task.

boa279
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Re: OBD II interface modification

Post by boa279 »

Im really looking for a way to get coolant temp, speed and rpm only. I'm really not interested in checking codes or clearing lights or any other information. I just want to be able to take the live data from those sensors only. Would your CAN solution help me learn what I need to kind of get started/understand whats going on there?

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Re: OBD II interface modification

Post by Benj »

Hello

The CAN solution might be overkill for what you require as it is intended as a complete course to get to grips with CAN technology. Instead you could use a MIAC controller (as this has built in CAN and large LCD) to connect to your CAN bus and pull out the values. The MIAC unit is also quite suited to a noisy in car environment whereas the EB006 boards will probably require some sheilding to work properly.

Here is a pin out for the OBD II socket.
http://www.auterraweb.com/obdiipinout.html

You will also need to find the relevant CAN messages for your specific car. This may be hard to find depending on your car but hopefully the details should be available online somewhere.

boa279
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Re: OBD II interface modification

Post by boa279 »

Id like to get a complete grip on CAN technology...Almost all of my projects have something to do with cars and it would be so amazing to stop using external sensors to get values when there are sensors in the car already. (and in better spots) I also design/etch my own boards so I would not be using the EB006 for anything other than programing and testing. The goal would be to learn how it works (I understand the principle) and be able to build a standalone project with out the need for eblocks. Is it possible to buy the CAN course itself with the CAN eblocks? Please let me know and thanks for the information!

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Re: OBD II interface modification

Post by Benj »

Hello

If you contact justin<at>matrixmultimedia.co.uk or sales<at>matrixmultimedia.co.uk then im sure we will be able to work something out to meet your requirements.

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