DIY ALDL cable VS Commodore help

[al7999]

Hi guys, new here. Been wanting to get into fault checking, data logging etc on my VS commodore V6. I was looking at getting an ALDL cable, but a mate who is a tech head said just make one (it's very easy) and got me some bits. Now he has gone away with work for a few weeks and I cannot get the cable working.

He got me the following chip (see photo). Said join the RXD/TXD together to go to pin 9 of the OBD interface. Then said connect the GND to pin 5 to the OBD interface. Job done.

I've go the chip set up correctly on my laptop, drivers all good, COM port all good. Efilive v4 not speaking with car.


From reading other posts on this site, it looks like I have to add a resistor and a diode to the RXD and TXD before they are spliced together? Is that correct?

Thanks in advance.



Chip can be seen on evilbay search: New 5V/3.3V FT232RL FTDI USB to TTL Serial Converter Adapter Module for Arduino

sku116803-17-.jpg (62.41 KiB) Viewed 5323 times

[VL400]

You will need to add a resistor and diode before linking the tx and Rx pins. Like this ... http://pcmhacking.net/forums/viewtopic. ... ode#p29140

Also watch out for the ftdi being a clone. The later drivers that ftdi released, and what windows loads automatically, will detect them and fail to return data.