FAQ:About OBD-II - Page 2

Dopefish · 04-13-2006, 08:33 AM

Quote: Originally Posted by shotgunefx

Not trying to steer this off OBDII, but I thought some of the new cars were sending that stuff over the CAN-Bus?

As an aside, my car (a 2002) uses a proprietary signaling system that's more or less I2C (called SWS) for everything (lights,switches,buttons) except HVAC.

From my limited understanding CAN-Bus is a manner of data transmission but OBDII is still the functioning source of emissions and troubleshooting data. The dataport is shared for the CAN-Bus IIRC. GM uses a special serial databus that their radio, HVAC, switch control, guages, etc go through which is great because it seemlessly integrates all the systems together. What is REALLY cool about them all being on a single system is that each item has their own controller so that you can say, plug in Pontiac Grand Prix guages into a Pontiac Grand Am and they will function normally. My friend had two sets of Grand Am guages running at one time in his car by running power and a connection to the OBDII connector for data. I wish my car had a similar system.

I have found my car is OBDI (transmission to OBDII was done midyear in the 240sx)... I'm actually happy though because my plans for turbocharging are now made easier being OBDI. Nissan's CONSULT system was boardering on being OBDII compliant to begin with so I still have many of the data benifits without the drawbacks.

~Kris

cliffloehr · 05-09-2006, 09:13 AM

I just finished building my own OBDII port interface from a kit purchased at http://obddiagnostics.com/ for $55. I also had to purchase about $15 worth of electronics and spend an hour or so soldering it together. Much to my amazment... it works! They also provide free downloadable software that can read and reset engine error codes, do high-speed data logging (3 or 4 samples per second), a cool-looking gage display and several other features.

My CarPC is still in the assembly state (on my work bench) so I used a 15' network wire as the serial cable. I was going to shorten it when the PC gets installed... but it's so cool, I think I leave it long enough to reach other cars... you never know when a friend might need an engine code reset!

JasonWW · 05-09-2006, 10:52 AM

Just wondering, can the OBD software be running as well as the stereo stuff? I have a dual head video card and was wondering if the main monitor could continue with all the entertainment stuff and I could add a smaller monitor somewhere and have it only display engine data. Like having a digital water temperature gauge, digital oil pressure, a more precise voltmeter etc... I THINK it would work. Anyone have any thoughts on this?

cliffloehr · 05-09-2006, 04:28 PM

Quote: Originally Posted by JasonWW

can the OBD software be running as well as the stereo stuff?

I've used dual monitors a lot and the only featur I've ever had problems with was showing video (including visualzation in Media Player) in the NON-primary display. So if you run your stereo stuff in the display marked "Primary" you should have no problem showing OBDII stuff in the other.

Grimoire · 05-20-2006, 01:50 AM

So Ive noticed alot of these readers are for 1996-2002, is there something that changed for 2003? I have a 2003 and I would like to get one of these Would it work? The site doesnt say. Ive googled for an answer, but to no avail. Is that what the CAN is that it wont support?

cliffloehr · 05-20-2006, 09:21 AM

Quote: Originally Posted by Grimoire

So Ive noticed alot of these readers are for 1996-2002, is there something that changed for 2003? I have a 2003 and I would like to get one of these Would it work? The site doesnt say. Ive googled for an answer, but to no avail. Is that what the CAN is that it wont support?

Hey Grimoire,
I'm pretty darn sure it would work for an '03. The OBDII protocol for Ford's OBDII port is PWN, and I can't imagine them changing it in 03'

I ordered the $55 version and had to spend about $25 to purchase additional electronic parts to solder onto the board and a project box to put it in. Also, I'm a little upset the OBDII connector did not come with the hood to cover the the wires. If I were to do it again, I'd just but the assembled product for $96

DavidIQ · 07-28-2006, 12:54 PM

I'd like to also add ProScan as a hardware/software for OBD-II. Connects to a Serial port though so you'd have to get a Serial to USB converter if your system isn't equiped with a serial port which most are not nowadays.

Info is here: http://www.myscantool.com/

Toehead · 08-01-2006, 11:52 AM

Also worth noting:
Just because you have OBDI, doesnt mean you can't build an interface cable. In fact, OBDI cables are much easier to make then the OBDII varieties.

Here are some sites to get you started:
http://winaldl.joby.se/
http://tunerpro.markmansur.com/
http://www.moates.net

With OBDI, you cannot modify the way the engine runs without buying a chip emulator from moates.. This emulator adds the reflash capapbility to the older ECM's, which use UV eraseable PROM chips instead of flash chips.
However, for 15 dollars at radio shack, you can build a cable that will allow you to pull your error codes, see all sensor data, and observe the general operation of your engine.

nickmr · 12-25-2006, 06:39 AM

I have a Chery Tiggo, and of course, the original sound gear is a crap and i want to replace it. Then the dealer told me not to do so because i can damage the "Computer" (refering to the OBD II systems) so the car will start misbehaving (just because they tried to install something once and got this result). Is that really true or they just don't know how to install car audio?

Brandtj · 06-28-2007, 07:30 PM

So then what type of software could you use to continually monitor your vehicles stats? I have the Proscan cable and software but it seems a bit buggy. I would like to integrate it into my font end app but not sure where to begin