Citroen Relay 2021 2.2 SS enterprise Ad Blue problem

[Tommohawk]

One other thing I should add. I wanted to confirm that there is no parasitic drain, so did some residual current tests yesterday. It's possible that this process, which obviously involves disconnecting battery and reconnecting through ammeter has caused an issue. I'll try the BSI reset method outlined on the forum when I get a minute and see if that helps clear the codes

[perfidus]

On my Relay van to reset the NOx errors I use Lexia tool and Diagbox. Another tool that works to get much of the live data and do resets is EOBD Facile app (paid version) on Android with a bluetooth dongle (VGate iCar Pro Bluetooth 4.0).
If you have two NOx sensors as the error indicate it (it's possible for Euro 6.2 vehicles) the first one is mounted in the engine bay right under the windshield and the second one is under the van, after the DPF. There is another topic on this, see viewtopic.php?t=87949.

[Tommohawk]

Sorry, bit slow, things happening. Thanks for that.. the NOx error issue is sorted in that the error code is clear and the no start message is also cleared using topdon artidiag 800bt2.
I've yet to retest the sensor function live.. it needs to get to operational temp to read anything and I need a longer run to do this. But I know now which sensor is the issue, how to replace it, and how to clear codes and reinitialise the sensor.
Big problem is that since replacing the old battery to eliminate any low voltage faults I have a a number of other DTCs. This is unrelated so I'll start a new thread to keep things tidy