How is fault code U059F fixed?

A typical diagnostic sequence used by mechanics, provided here for educational reference only. Diagnostic work should be performed by a qualified mechanic with the appropriate tools and training. 1. Read live NOx data for both sensors on a capable scan tool and compare them. If sensor B reads stuck, wildly out of range, or shows no value at all while sensor A looks sensible, you've found your problem area 2. Pull all stored codes, not just U059F. SCR efficiency codes and AdBlue dosing faults often sit alongside it and change the whole diagnosis 3. Inspect the sensor B connector and harness for green corrosion, moisture, melted insulation or a bent pin. Unplug it, check both ends, this catches more of these than people expect 4. Back-probe the sensor power supply and ground with a multimeter to confirm it's actually getting a clean feed before you condemn the sensor 5. Check the exhaust around the sensor for leaks, heavy soot or AdBlue crystal build-up that could be skewing the reading 6. Clear the codes and road test over a proper run including some motorway, then recheck whether U059F comes straight back

Invalid Data Received From NOx Sensor B

Jump to the fix

Severity

Medium

Can I keep driving?

Usually drivable, but get it diagnosed without delay.

First step

A typical diagnostic sequence used by mechanics, provided here for educational reference only. Diagnostic work should be performed by a qualified mechanic with the appropriate tools and training. 1. Read live NOx data for both sensors on a capable scan tool and compare them. If sensor B reads stuck, wildly out of range, or shows no value at all while sensor A looks sensible, you've found your problem area 2. Pull all stored codes, not just U059F.

UNetwork
0Generic code
5Network / Communication
9FSequence number

What does it mean?

U059F is a Network (CAN bus, module communications) fault code. It indicates: Invalid Data Received From NOX Sensor "B" . This is a standardised OBD-II code. The technical definition is the same regardless of the make or model of vehicle, although specific causes and symptoms can vary between vehicles.

Symptoms

Likely causes

How to fix it

Codes From the Same System

All Fault Codes

Related Similar Codes

This information follows the generic OBD-II definition and does not replace a vehicle-specific diagnosis. The severity rating is rule-based; an authorised diagnostic reading is required for a definitive answer.