NOx 'B' sensor U029E error

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My Name: stevet1

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Joined: Fri Feb 04, 2022 4:36 pm
Model: C3 Picasso
Year: 2016 (66)
Engine Size: 1.4 (16v)
Fuel Type: Diesel
Mileage: 80000
Trim Level: NA
Gearbox: Manual 5 speed
DPF: Yes
LHD or RHD: RHD (UK)
Engine name: BlueHDi (100 PS)

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Hi

Hope someone can help! First time since new my C3 Picasso has gone wrong. First indication was service and engine managent system AND urea lights all came on at 9nce, with the urea light flashing. Diagnosed U029E error code, NOx 'B' sensor. Had the sensor replaced at a non-dealer garage, but the error won't clear.

I believe I won't be able to start the car 150 miles after the error first showed, but I am not sure and don't get a distance warning on the dash.

So......do I need to do something so the car recognises the new NOx sensor, or could it be a fault with the wiring somewhere. Also, am I right it won't start after 150 miles?

Thanks!
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My Name: Arfur Dent

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Model: C3 2002-2005, Original shape model
Year: 2002 (52)
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Hi

U029E is a communication BUS error and not necessarily a faulty sensor error.

I am not surprised that changing a sensor that doesn't show a fault doesn't clear error.

Check the wiring to the system at fault with U codes and don't go straight for the sensor itself which would be more prone to give a P code.



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My Name: routemaster1

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Model: C3 2017-on. The new C3
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The Adblue countdown ususlly starts at 1500 miles. May be worth ensuring that there is sufficient Adblue in the tank before continuing. From my time on another Citroen forum, I am aware that sensor or sensor wiring issues can cause the Adblue warning.
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