on my XR8 I was trying to set up an air/fuel mixture guage to tune her properly, when I used the diagnotic connector self test output pin for a battery voltage when ign on, there is no voltage at all?
according to a manual I have ,this is supposed to be battery voltage with ign on, but theres nothing.
could this have something to do with my car being so variable with power, sometimes it seems to go a s**t harder than others?

The only battery voltage on the diagnostic plug (which I don't think is regulated [apart from battery]) is the very last pin on the bottom.

And I don't think Engine STO is meant to have a voltage unless its in diagnostic mode? im not sure on that though.

Why are you hooking it up through that?


Cheers