Ok, I have the whole circuit built and its in a relatively small area, roughly 2" by 1" using the "Proven MAX232-based GM ALDL Interface Circuit" By Andrew Mattei. I believe everyone knows what I am talking about now. I got the ALDL plug and the last few connections are still confounding me. I asked this question a few weeks ago but only got a short and vague answer to my questions.

On the car side pinout this particular schematic has connections at 1,3,5,13 on the computer plug used in the schematic (These look important because they are connected directly to parts of the circuit.) The other conections are on the other side of the plug... they don't seem important.

Craig mentioned that I should only have 2 connections. There are 4 connections that are directly linked to a part of the circuit though. pin 13 goes to the D5 diode. pin 5 goes to the collector of the Q1 transistor, and pins 1 and 3 are straddled by the R9 resistor. So do I simply eliminate the R9 resistor? Do I eliminate the connection at pin 13 from the D5 diode and simply leave these parts on the circuit unused? Also whats this I see about ALDL diag. (B) on 165 ECM's only.
Perhaps Craig thought I was using the 730 instead of 165.

 

Yeah, thought you were looking at a 730 job.

The 165 will require the connection of the pin-B to the circuit, which will give 10k resistance between pin-b and ground.

The power supply may come from your PC port, in which case you won't need the pin 13 or 25 connection.

Hope this helps. I'd try it without the power supply first, but you'll still need the 10k across A&B.

-Craig

 

craig

im selling my snap on scanner and trading it in for a lap top and scannng software. do you sell cables still ??? if so youve got my email.
djfreggens@aol.com
thanx

 

Ahh! Thanks Craig, Thats what I was wondering. So it appears that the power supply could be supplied from either side hence the funky setup heh. I will finish the cable up soon. Thank you so much

 

Where can I get ALDL plugs?

 

Go to www.summitracing.com and search for this part number.

AXY-20110 It cost about $37 shipped to my door.