OBD2 -> USB Cable
Dad’s Holden Rodeo started burping and farting and throwing codes on him recently, and it made me think how much I’d really like a scan tool. I still couldn’t afford a decent handheld one, and my current car doesn’t even need one so it’d be a bit of a waste.
But then out of curiosity I did some poking around and found an ELM327-based USB cable online from China for next to nothing and decided just to go for it. It got here yesterday, and we did some poking around in Dad’s ute with it (despite the fact the ute’s already been fixed).
When it arrived in a quaint little bubble mailer, with a half-size CD full of “software”. It included the drivers for the USB->RS232 chip that’s on the USB side of the device, which passed an AV scan and installed without a hitch.
I poked around with a trial version of PCMScan I’d already downloaded, but it started coming up with a lot of garbage data. “Uh oh,” I thought. “This is what you get when you spend the price of a pizza on a diagnostic tool.”
I took a look at some of the other software on the disc, and happened upon a pirate copy (complete with keygen) of another OBD2 program and after pondering it for a while, scanning the files with AV software, I decided to give it a shot. It turns out that apparently either the version of PCMScan I got was busted, or it doesn’t like my ELM327 cable, or the combination of the two doesn’t agree with Dad’s Rodeo. The other software worked perfectly as advertised, including picking up the VIN correctly and having accurate readings on all the gauges.
Next I started looking at FOSS alternatives, because I didn’t see the sense in buying $100 worth of software if there’s a version that I can hack on… and there is two projects that looked promising, as both are C++/QT based and that’s familiar turf for me from having hacked on Mumble a lot. Unfortunately one of them (OpenOBD) won’t even run, and OBDToolbox runs but refuses to speak to my ELM327.
I’ll experiment with the latter some more, when I get time… if I can make it speak and start contributing to it, it could be a promising project. Thus far it looks like it’s in a semi-complete, “works for me” stage, to which I would hope I could at least bring it to a “works for me too” stage and from then on it’ll grow of it’s own accord. Unfortunately I’m a bit short on time to really dig into it now.
Update: Apparently it doesn’t work on V6 Commodores prior to the VE either. :(