Thanks for that longassname, that looks much more simpler to create than the board I've made, and probably a lot more compact as well.
Just a few questions, what diodes are you using?
I take it the Diode "leg" of the drawing with resistor/gnd/5V joins onto both the RX and TX "leg"?
Im just a bit unsure as there is no dot to connect or a bridge to go over, but it looks fairly simple, what else would the thing be doing there!
Also what variation of the line driver are you using, I just noticed Philips makes a whole range, as does TI. Are you using the same chip twice (I noticed some support more than one line, bit like the Op-Amp) or two seperate chips?
Also interesting to see you've done both the RX and TX lines, is this really necesary? The data from the FTDI should be clear and strong, it was just the reply from the ECU that could turn into garbage at times. I suppose its better to be safe than sorry though.
Anyhow, great work, thanks for sharing
Cheers,
Daniel.