service engine on - but no codes?

[Ashaman074]

OK, so 11.9v not running, 14v while running.

However, after hooking up the code scanner again, I noticed that out of 112 PIDs, only 4 are showing up. This seems very bad to me...

Looking at live data for example, you would normally see all sensor readings, but I have only MIL status, engine speed, vehicle speed, volts, and OBD2 State. Further, if I read all the codes, and then check the categories, all others are showing up as "n/a."

I believe this is why it isn't showing any DTCs; as none of them are available. The scanner is communicating, but only very limited information is being passed.

Is it in some sort of fault mode or something? The dash reports everything is "OK" as well; no indication that it is in some fault or fail-safe.

Thanks.