Nox Sensor Communication U100600

[jpg98]

Hello,

My 2014 Passat is out of warranty now and I'm having an issue with the Nox sensor. I have code U100600 NOX Sensor 1 Bank 1 No communication.

I purchased a new sensor/controller and it's still doesn't seem to be working. NOX Sensor Bank 1 Sensor 1 shows 65535 ppm at all times.

A check of the wiring found voltage on the appropriate pins of J583 on the NOX controller and I verified the signal connection pins (3&4) back to the ECU.

Any suggestions? I suppose it's possible I received a bad part, but it is an OEM sensor.

Thanks.

 

[jpg98]

I scoped the CAN wires (3&4) and it seems the comms are present. I also checked power and grounds again just to be sure.

Here's what looks strange to me:
NOx Sensor Concentration Bank 1 Sensor 1 Data Availability: Results available or MAX value because of sensor fault
NOx sensor bank 1 sensor 1: 65535 ppm

I don't have an active fault right now, but I expect it soon.

Does this sound like a bad sensor?