This could be a big or a small job, I don't know as I'm not a developer but...

Is there a developer out there that is familiar with the OBD2 protocols and connectivity with a car's ecu?

I would like an application that will connect via bluetooth to a bluetooth OBD2 adapter so that I can have a realtime visual on my car's engine management system.

An app that is available for Palm and Windows is OBD Gauge (http://www.qcontinuum.org/obdgauge/), but being a maemo device I want to take it further, in someways to give mechanics an alternative way to look at a car's information.

Check out CarMan. I think it's either pretty close to or actually is running now on the N900.

http://www.youtube.com/watch?v=nu5HeYEDTxk

How about Carman?
It's getting there... I hope. I use it with my N810, but waiting to use it with N900 as well.

Thanks guys! Didn't realise that this existed!

+1 for this, i think there is another post regarding this, someone put this link http://www.dealextreme.com/details.dx/sku.16921 which is a bluetooth adapter to work with the handset..

The fundamental protocol of most of these devices is quite simple.
>90% use http://www.elmelectronics.com/dsheets.html chips, look at the datasheet for the elm327.

In principle, you could just use the above mentioned bluetooth adaptor from DX, and your favourite serial terminal program.
For some things, such as reading out fault codes, or resetting check engine lights, this would be quite adequate.

Carman was a good start/attempt for N8x0 series... I don't know how far anyone's got porting it to the N900... I don't know why they'd try to be honest with you. From a development point of view the amount of work required to port over the entire enlightenment engine (that Carman's built on), VS just building a new app from scratch just doesn't make sense.

So on that note Spenc3 and I have started the Carocell project; interfacing to obd2 is dead easy, as already pointed out... the tricky part is handling all the automatic setup/teardown of bluetooth, and of course having a nice flexible GUI system for handling and displaying that info.

At the end of the day the only really practical use is for reading trouble codes and clearing them, which is the most difficult part of an app because it requires you to do a bunch of binary comparisons and evaluations in order to determine exactly what's what. Anyways long and short of it is that there are people working on it...

i have used carman , but still use my e66 whit obdscoop , whit obdscoop you can erase error;s and clear out f,exs check engin light

did send a mail to obdscoop and ask if he was going to make it for maemo but that was no plan for that

but if u have a symbian phone and the obd2 bluetooth adapter
it is a great app if u have a car whit obd2

regards
Just

OBD on my n900 would be awesome, I hope this comes to fruition

once you have a prototype i will be willing to test it for you (i'm a mechanic buy trade so plenty of vehicles at work to test on) would be good to have a range of programs to check ecu's carman is the only one i can think of at the moment thats about and works on the N900