Ok thanks, i will have to look at it closer but I believe it is pin 2 in my truck. Which would be weird to have them on different pins in different vehicles.
I have to assume that voltage regulator needs a significant heat sink too.
I just hard wired an ODBII unit to my car and I was a bit surprised to find out that there were only 4 wires.
It looks like I will be trying to build an ODBII replacement with one of the new "bad" project boards. No sense in using an $80 board when a $9 and some hardware will do (hopefully).
My ODBII unit is normally tied to pin 2 but it is a "high" with a low at a different pin which is unused in my truck. (Similar to the Can +, Can - setup.) Does it matter which ground you use for the reference for the GMLAN?
I tied the "low" pin to the Signal ground although I probably could have just left it unhooked. Still in process of wiring my truck and not sure when I will be receiving the project board. I look forward to tying this into my ODBII connector and trying to communicate. I have an ODBII cable that came with the ODBII chip I have. I haven't powered up the truck PC yet to see if the standard ODBII unit is working. I have a logging program so I will be able to monitor my attempts at communicating with the Propeller and your object. I may try working it so I can get the Propeller to work the same as the ODBII unit that I have. It uses Hayes style AT commands to make changes to it. Would be kind of a supercharged ODBII connection that way.
Comments
I have to assume that voltage regulator needs a significant heat sink too.
Rodney
It looks like I will be trying to build an ODBII replacement with one of the new "bad" project boards. No sense in using an $80 board when a $9 and some hardware will do (hopefully).
My truck (2003):
Pin 2 - GMLAN
Pin 4 - Chasis ground
Pin 5 - Signal Ground
Pin 16 - +12
My ODBII unit is normally tied to pin 2 but it is a "high" with a low at a different pin which is unused in my truck. (Similar to the Can +, Can - setup.) Does it matter which ground you use for the reference for the GMLAN?
I tied the "low" pin to the Signal ground although I probably could have just left it unhooked. Still in process of wiring my truck and not sure when I will be receiving the project board. I look forward to tying this into my ODBII connector and trying to communicate. I have an ODBII cable that came with the ODBII chip I have. I haven't powered up the truck PC yet to see if the standard ODBII unit is working. I have a logging program so I will be able to monitor my attempts at communicating with the Propeller and your object. I may try working it so I can get the Propeller to work the same as the ODBII unit that I have. It uses Hayes style AT commands to make changes to it. Would be kind of a supercharged ODBII connection that way.
Rodney
Rodney