AdBlue and SCR off explained

How SCR works

AdBlue is injected into the hot exhaust upstream of the SCR catalyst. It breaks down into ammonia, which reacts with NOx to form nitrogen and water.

NOx sensors before and after the catalyst let the ECU check how well the system is working. A low AdBlue level, a failed dosing system or a poor catalyst all lead to faults.

What an AdBlue or SCR off file changes

An AdBlue or SCR off file changes how the ECU monitors and controls the dosing and NOx systems. It stops the system being reported as faulty when it is not working as expected.

BRV Tuning supplies the binary only. Any removal of dosing hardware or tanks is outside our service.

Emissions-related files are supplied for off-road, competition, agricultural and export use only, and must not be used on public roads.

AdBlue / SCR off, standalone

Pricing: Master file price €82 ex VAT · slave (Tier E) €49.

Ordered on its own. Send the original read and the ECU part number, and state whether the dosing system is fitted.

Common codes

• P20EESCR NOx catalyst efficiency below threshold (Bank 1). The AdBlue (SCR) catalyst is not reducing NOx as well as expected.
• P2201NOx sensor circuit (Bank 1). The NOx sensor signal is outside the expected range.

AdBlue / SCR off, with a stage

Pricing: Master file price €47 ex VAT · slave (Tier E) €28.

Sold as an add-on inside a Stage job at a lower price than the standalone file.

AdBlue / SCR off, truck and agricultural

Pricing: Master file price €200 ex VAT · slave (Tier E) €120.

Heavy-duty SCR calibrations are priced separately. The off-road notice applies. See the truck and agricultural guide.

Symptoms people usually report

• A low-AdBlue or dosing fault warning on the dash.
• NOx sensor faults after a sensor or harness change.
• Reduced power or a countdown to a start restriction when a fault is active.

Before you order

Check the AdBlue quality and the dosing system first. Poor-quality AdBlue can cause a fault a file cannot fix.

Results vary by engine, fuel, condition and supporting hardware, and no gain or outcome is guaranteed.

Common fault codes

Codes vary by make, model and ECU. Read the stored codes on your own car before and after flashing.

• P20EESCR NOx catalyst efficiency below threshold (Bank 1). The AdBlue (SCR) catalyst is not reducing NOx as well as expected.
• P2201NOx sensor circuit (Bank 1). The NOx sensor signal is outside the expected range.