OBD MPGuino gauge

[mattjreilly]

I checked the K line and it is going high and dropping down to zero, I'll see what I can do to read what I'm getting from the car.

Thanks Froggy.

Matt

[Froggy]

So the TX function is working fine.

Just check for ANY reply... it may be that the car is replying with something else than what we expect.

[dcb]

Here's kinda what I was thinking for adding L-line support, basically add a "gate" that replicates the k-line output on the L-line, dunno if it works or breaks stuff, just thinking out loud. Needs a minor code tweak to utilize. R3 might need to be 5k or something too.

[Froggy]

Ha! You guys are gonna like this!

The Toyota Matrix 2007 does NOT need the L line to initialize!

Last night I made up a dedicated L line interface, removed the K to L jumper and used the new interface, rebuilt the software and... it failed. I verified I was getting voltage on the L line and K line during init... yet it did not work whereas the jumpered K to L line set up did...

Hmmm...

I noticed that the resister I used in the original set up was not labeled as a 520, even though the packaging had labeled it as such. I swapped it out for a 560 I had on hand, disengaged the L line interface (unplugged from the Arduino), and ... the K only interface worked like a charm...

I guess the jumpering the K to L line brought the K line into spec to become within tolerance and accepted by the car...

So... now I will rebuild the K line interface (one single 33290 chip) and go from there (I don't have any valid 520s, but the 560 seems to be acceptable - and no stores around town carry any.)

[dcb]

[Mesuge]

Froggy> Congrats! And thanks for the reminder, yes the extended ScanGauge
OBD<->RJ45 will save a bit of space in comparison to RS232 for the same price ~$20. Also lowrise Freeduino with USB mini-B connector helps..
ScanGaugeII - Scan Tool + Digital Gauges + Trip Computers
ScanGaugeII - How to Buy

I'm glad that the ISO connection horror stories did not turn that bad afterall,
that put me away for some time..

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Has anybody considered placing these control buttons on the steering wheel for easier/safer driving? But that would demand some sort of wireless comm. or heavy disassembly of the wheel..

Perhaps hacking this SNES Remote ($5) featuring joy + 6 other buttons.
http://www.adafruit.com/index.php?ma...roducts_id=131
http://upload.wikimedia.org/wikipedi...Controller.jpg

wireless hack to this SNES controller (433MHz ASK based):
http://hacknmod.com/hack/how-to-wire...o-controllers/
http://www.ppl-pilot.com/
http://cre.ations.net/creation/wirel...roller-for-wii
/obviously we need much smaller batt. so the size/price goes down..

or something similar to these basic 4channel RF controls:
http://electronics-diy.com/


hacking OEM Audi 3x button remote assembly:
http://blogs.ebay.com/rcjoycon/entry...QQidZ868332015


Some RF links 3-400Mhz from Arduino shop (probably single channel):
http://www.seeedstudio.com/depot/433...kit-p-127.html
http://www.seeedstudio.com/depot/315...-kit-p-76.html
http://www.seeedstudio.com/depot/2km...der-p-321.html

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adding sensors to the mix, for instance:
-compass heading (Hitachi HM55B <$30)
-GPS or connection to handheld unit via GPS/NMEA parser called TinyGPS
(!reading from multiple soft serial devices via NewSoftSerial library, Arduiniana.org)
-DCF77 based radio clock ("atomic time")
http://www.arduino.cc/playground/Mai...Hardware#Input

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Btw. was there any follow up to that nice Graphic LCD 128*64 (KS0108)
mod - as posted way back approx. around page #21 ??
http://public.fotki.com/HULK77/ks0108/dsc0038.html

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Ladyada's tutorial on Arduino and parallel char. LCDs connection:
http://www.ladyada.net/learn/arduino/lcd.html

[Froggy]

Thank you. It was really nice to see I didn't require the L line. It's too bad I had an incorrect resister in my order as it caused a lot of stress.

I am happy with the J45 connection. If someone else is doing one, use an OHM meter and use that to find your power, ground, and K line outputs. J45 modules can have the plug in alternate orientations. Of the two connectors I have one is 1 -> 8, the other is 8 -> 1... Use the Ohm meter to verify exactly the pins you need and where they are on the circuit board. (Especially if like me you've put the connector on a standard circuit board which forces the pins out of the staggered array.)

Ummm... Putting the buttons on the steering wheel for SAFE driving? How can this work? If you're playing with buttons, and reading displays, you're not looking out for the child running out after their soccer ball. Save button pushing for when you are stopped and you can safely move your hands off the steering wheel and your eyes off the road. Saving a little bit of fuel is less important that safety.

Welcome to the project, I wish you success at first hook up!

[Mesuge]

Thanks for the details about wiring. That SNES remote controller would be gutted to minimum size, imagine similarly working buttons on luxury cars, they have got buttons all over the wheel.. It's intuitive you just look on the road and then refocus momentarily on the scangauge/mpguino as you toggle the functions, no need to look at the 3rd point - steering wheel at all..

[Froggy]

I see your point on what you want to do. It's certainly something to think about and you could possibly develop it if you felt the need for it.

May not even need to be wireless if you could feed a wire through the steering column assembly out to the Arduino. That would not require any software changes.

[gyb]

Hello all,

This is a great project. I'm also interested in building a OBDuino and I've already ordered the parts. My car is a Hyundai Accent year 2000 model car imported to my country from Singapore. It supports the ISO9141-2 and OBD2 complaint. But I have one problem. Though the ECU returns
VSS as a supported PID when queried, it always reports 00 as the value not the actual speed. I have checked using a hand-held OBD2 scanner, ELM327 based USB interface and by sending AT/OBD commands through Hyperterminal. ECU reports "NO DATA" for other unsupported PIDs. This car has Vehicle Speed signal in pin 14 of the OBD2 connector.

While reading this thread I saw Magister complaining his car (Hyundai Elantra) not reporting VSS and he seems to have resolved this problem.

My speedometer works fine. It gets the VS from a VSS sensor. This same signal goes into ECU and pin 14 of OBD2 connector.

Is it possible for me to get VSS from pin 14 of obd connector and integrate that in to the program?

Thanks for your work.