Need a mechanic's opinion on an OBD2 port that won't connect to a reader.

[alice_thomasc]

My 2008 Rio JB is mine. Although it won't work with the vehicle, the OBD reader can connect via Bluetooth. These three readers won't connect to my vehicle.

This car is a dream to drive.
Although the engine light is off, the oxygen sensor light turns on when disconnected. The light goes out as soon as I reconnect the oxygen sensor. This means the system is operational.
I don't understand why my OBD reader won't reconnect.

Everything appears to be in order after I checked the voltages and continuity of the obd port.
The continuity test between the ECU plug and the OBD port came back negative.
Even with an adapter that goes from the engine bay diagnosis port to the OBD port, I can't get it to work.

Does anyone have any hints as to why I am unable to establish a connection?
I am grateful.

[aidencr]

Quite peculiar. It would be helpful to know which OBD reader you're using. Both the Foxwell NT530 and the OBDLink LX have been fully functional on my 2009 Rio, which is an Australian model.

[alice_thomasc]

I appreciate your feedback.

One is a cheap plug-in reader from AliExpress, and the other is a bluetooth reader. My Hyundai was read by both of them. I suspect a data relay problem, but I haven't had the chance to test on another 2009 Rio. Not an issue with the reader.

[tariqsm]

There was a period when my ECU was having issues and my OBDLink LX wouldn't communicate. Following the repair by the ECU repair shop, I was compelled to jumper my fuel pump relay.
The ECU is operational once again, and my OBD can communicate.

Even the Shop professional grade reader failed to function on the elektro engine.

[tariqsm]

https://www.facebook.com/engineelektro

[tariqsm]

What if we tried connecting the OBD to a different vehicle?