Can't connect to the PCM with my HPtuners, says no power at the diagnostic connector. Does anyone have the pinout or wiring diagram for it so I can trace it?

Thanks,
Jonota

For what car?

Check the "CIG/ACCY" fuse, it powers the DLC port.

For a 1998 Z28 (sorry), I'll check that fuse, the lighter plug-in doesn't work, could that also cause a problem...

Interestingly enough someone was able to pull codes out of it not too long ago... hmm.

Thanks for the inputs guys

Jonota

They're on the same circuit so the fuse is blown. If it blows immediately I'd look at the lighter ports, or whatever cell phone cord, etc. was plugged in.