Fitment (Verified OEM Cross-Reference — NO guessing added)

Based on OEM Ford parts listings, Continental SNS977A catalog data, and multiple aftermarket EPC references, this NOx sensor is used in Ford diesel SCR (AdBlue) systems, mainly on Transit / Transit Custom / Transit Connect EcoBlue Euro 6 platforms (V362 / V363 generation depending on engine variant).

Common system applications include:

• Ford Transit Custom 2.0 EcoBlue (Euro 6 SCR)
• Ford Transit MK8 / V362 2.0 EcoBlue diesel
• Ford Tourneo Custom 2.0 EcoBlue
• Ford Transit Connect EcoBlue (selected SCR variants depending on engine/output)

Fitment is strictly based on OE number matching:
LK21-5L248-AC / SNS977A / A3C05714000-02

OE cross-reference listings confirm this is a Continental SNS977A NOx sensor used in Ford Transit EcoBlue SCR systems, commonly positioned as upstream or downstream NOx monitoring depending on exhaust layout.

Technical Description

This NOx sensor measures nitrogen oxide (NOx) concentration in diesel exhaust gases and sends real-time data to the ECU.

It is part of the SCR (Selective Catalytic Reduction) system, which uses AdBlue (urea solution) to reduce NOx emissions and meet Euro 6 standards.

The sensor operates in high-temperature exhaust conditions and communicates with the ECU via integrated electronics for continuous emissions monitoring.

Symptoms / Fault Codes

• Check engine light
• SCR / AdBlue system warning
• NOx sensor communication failure
• P2200 / P229F / U029D type codes (Ford-specific variations)
• Reduced engine power (limp mode)
• Increased emissions

OE / Part Numbers

• LK21-5L248-AC
• SNS977A
• A3C05714000-02
• LK215L248AC (format variant used in aftermarket listings)

FAQ

Is this sensor vehicle-specific?

Yes. Ford NOx sensors are ECU-calibrated. Even small suffix changes (AC / AD / AG revisions) can change connector shape, cable length, or software pairing.

Why do Transit models share similar sensors?

Because Ford uses shared EcoBlue diesel SCR architecture across Transit, Transit Custom, and Transit Connect platforms.

Can similar OE numbers be used instead?

Not recommended. These are emission-critical ECU-coded components and must match exact OE specification to avoid SCR faults, limp mode, or incorrect NOx readings.