Bench harness and LS1 edit unlimited
Thks
Thks
I did so for the 97/98 PCMs and one for the 99 to present PCMs to do "off board" tuning.
Last edited by Simpson Speed; Feb 15, 2004 at 10:33 PM.
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http://www.akmcables.com/98-PCM.htm
LS1.com removed it from their web site.

You can build a benchtop harness pretty cheaply - GM sells the LS1 connector for about $20, and then you need some PCM pins (I think they're about $.75 ea, or you can use cut ones out of harnesses).
For a 98 PCM, all you need is:
Ground - Blue 21 & 60
+12V - Blue 19, 20, 61
Data on Pin Blue 58
This is NOT THE SAME as a 99+ PCM. Do not use this pinout on them. You'll kill the PCM. You'll need to move a few wires around.
Note that you only need the blue connector.
My benchtop harness is homebrew, ugly, but it works fine.
Andrew

BTW, Your OBD1 cable you made me years ago is still going strong.

I just use an old 300 watt PC power supply. They have pretty decent voltage regulation, and I've had no problems with it. As far as the wiring goes, I can't remember exactly...but on the "411" PCMs, you'll only be needing to use 6 wires on the "Blue" header.







