ISX 11.9 Code 3232

[TBird556]

2012 Kenworth with a ISX 11.9 CM2250

Have a constant code 3232 displaying (Inlet NOX Abnormal Update Rate). Truck came to my customer with no previous history, tested voltages and CAN hi/low at pigtail. All within spec so installed new sensor. (RX sensor from local dealer, no new ones in stock at time). Still have code displaying. Installed new pigtail hoping a weak contact on pins, still having fault code. Followed Quikserve trouble shooting and have tested the harness for hours trying to locate harness issue. No faults found. Updated ECM twice( already had latest calibration, but was hoping for software bug). Everything on the CAN wiring ohms out to proper specs. Resistor good, VGT good. Pulled ECM out and gave to local vendor for bench test- all they stated was ECM communicates properly. Inlet NOX fuse good, no faults in fuse box. Relay triggers and supplies voltage properly.

Can a faulty ECM pass a basic bench test and still not work properly in the truck, or am I missing something else in the harness?

ESN- 75007311