OBD port not working even though there is power
 

2008 Z06. Port has power. I verified using multimeter. 12v between pins 4 and 16. Scanner says no ECU connection. I have aftermarket throttle controller and revmatch installed. Not sure if these could be interfering. Port used to work even after install of those two components. I sometimes get the reduced power message and I used to be able to clear it on the fly with my bluetooth OBD dongle but cannot since the OBD port stopped working.

So you’re saying you are getting “PCM NO COMMS” ??...any DTC’s ??...anytime you get a module no comm it’s time to start checking power and grounds on that module !!

No DTCs no nothing. no connection. disconnected vitesse controller since folks have been having issues with that module but that has not fixed the problem. OBD port does have power.

I don’t know what kind of scan tool you’re using but if you can see if you have comms with all the other modules...if just the PCM like I said...power and grounds !!

You have a blown fuse, I'm not sure which one but check your fuses.

already done that. no blown fuses. no problems since the vitesse was disconnected.

Not being a smart ass but is ignition in RUN and not ACC?

Try disconnecting the battery, waiting a little and then reconnecting it. It worked with my car for some reason.