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High Nox Reading — Possible Fault Codes

Found 1 fault code associated with high nox reading. Codes are sorted by severity — check STOP ENGINE codes first.

SPN 4342 FMI 4
NOx Sensor Outlet
Detroit Diesel DD13 • Component: NOx Sensor (Outlet) / Wiring • J1939
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⚠️ Diagnostic Note: Symptoms can have multiple root causes. Always verify with a diagnostic scan tool before replacing parts. The fault codes listed above are possible matches for high nox reading based on SAE J1939/J1587 fault code definitions and OEM service documentation.