obd 2 port not working at inspection station.

[Rcick Grimes]

Recently bought a 2014 rs5. Went to get inspected and when they hooked up the machine to the obd port they couldn't get any reading. I know the port works as the car came with a valentine one built into the mirror and it gets it power from the port. The only other thing that came already installed in the car was a vent mounted P3 gauge. When I bought the car the dealer said that gauge needed to be disconnected for inspection in that NY but I had them reconnect it since I never heard of such a thing in my state (NJ).

Any chance that P3 gauge is causing the inability for the state inspection hook up to be able to read it and thats what the dealer was trying to explain? Anyone heard of an issue like this before?

[Smac770]

How is the P3 connected? Does it plug into the port? If it works and is displaying data, then the port works. If it's hard wired into the wires of the backside of the port, could be.

You might need to check the power on the port pins. With ignition on, you should see 12v on pins 1 and 16, and ground on pins 4 and 5.

There's not much you can do to test the concern if you don't have a scan tool of your own to attempt interacting with the J533 (control module on the other end of the CAN lines on that port).

[Rcick Grimes]

Appreciate the reply. Been doing some research and I believe the issue is the obd2 port cant have 2 things trying to communicate with it. The gauge apparently has a setting to switch to analog which keeps it drawing power but not actually communicating with the obd port. I think putting it in this mode or just disabling it should solve my issue.

It is hardwired to the port as well. Figured Id update this post for anyone in the future who might search for this issue as well.