I looked into the OBDscan and CANscan products from Harrison. The problem with them as far as I could tell was that you had to buy two pieces of hardware to cover the entire spectrum of OBD protocols: J1850 VPW, J1850 PWM, ISO 9141-2, ISO 14230 (also known as Keyword Protocol 2000 or KWP) and ISO15765 (also known as CAN, mandatory in 2008 I believe). I also looked at the ELMscan stuff too--cheap but no support for CAN.

The Multiplex Engineering product on the otherhand supports them all with one cheap device. However, it's a real DIYer and doesn't come with any software. There might be other software packages out there, but OBDGauge was the only one I found. Unfortunately, it doesn't support the CAN functions from ME but that can always be fixed with a little coding (OBDGauge is open sourced with a GPL license). One nice thing about the OBDGauge software is that there are versions for PalmOS, Pocket PC and Windows.

I agree with DaveB's assertion that this is a must for the DIYer. You can compute tq and hp curves from the data as well.

BTW, our cars are ISO 9141-2, but we also have CAN pins on the DLC for anybody that might be searching.

 

So what's the best value for an OBD II reader for the Palm? I could also use my laptop if it gets me a more useful tool for reasonable cost.

Website links appreciated.

TIA

 

ckg35, it depends on how much you value ease of use. The ME + OBDGauge products are cheap but not so easy to use.

BTW, the ME product came in and I gave it a try. It turns out I was wrong about the OBDGauge software in a pretty big way. The portion that runs on Windows does not actually connect to the device, but instead only graphs and exports to CSV files logs created with a Palm or Pocket PC device. I was able to work around this by running the Palm component in a Palm simulator (http://www.palmos.com/dev/tools/simulator). This allowed me to connect my laptop to the car since I don't have a serial hotsync cable for my treo.

I have a performance question for people using other devices. How fast are your devices reading data from the car?

 

Holy Cinder Blocks, Batman!

I didn't know they made a Commodore 64 laptop!

 

The CAN bus data stream is proprietary. Your stuck with the slow ISO protocol for OBDII sensor data. If anyone finds a CAN bus solution for Nissan cars, it will be a great find!

 

I'm working on it. I wrote a perl script to query over ISO partly as a learning exercise but also to get more flexibility in grabbing the usual OBD params and present the data. Once I flush it out for the mode 1 params I'll get started on the CAN data.