P24C0 — NOx Absorber Catalyst Efficiency Below Threshold

What P24C0 means

NOx Absorber Catalyst Efficiency Below Threshold. Common causes: NOx catalyst not meeting conversion efficiency.

How serious is it?

Serious. Power derate likely — plan to stop soon.

Most likely causes

1. NOx catalyst not meeting conversion efficiency
2. Catalyst sulfur poisoning
3. high exhaust temp damage

First moves (roadside)

1. Perform desulfation procedure
2. check EGT sensors for catalyst thermal event

FAQ

Related codes

Codes that commonly appear alongside P24C0, or share the same subsystem.

• SCR Operator Inducement — Severe Derate Active (SPN 5246 FMI 0)
• Aftertreatment 1 Diesel Particulate Filter Differential Pressure - Data Valid But Above Normal Operating Range, Most Severe Level (DPF severely restricted / plugged) (SPN 3251 FMI 0)
• Aftertreatment 1 Diesel Exhaust Fluid Quality - Data Valid But Below Normal Operating Range, Most Severe Level (DEF quality/concentration incorrect) (SPN 4364 FMI 1)
• DPF Differential Pressure — Data Erratic (SPN 3251 FMI 2)
• DEF Dosing Unit — Not Responding Properly (SPN 3361 FMI 7)
• SCR Conversion Efficiency — Below Threshold (SPN 4364 FMI 18)
• DEF Quality — Out of Spec (SPN 4094 FMI 31)
• EGR Temperature — Too High (SPN 412 FMI 0)

Same symptom: DEF / SCR fault

Other codes in the DEF and SCR chain — the ones that end in an inducement countdown.

• Reductant System Performance Bank 1 (P204F) · Aftertreatment & Emissions
• Reductant Quality Deviation (P20EA) · Aftertreatment & Emissions
• DEF tank level low (SPN 1761 FMI 18) · Aftertreatment & Emissions
• DEF tank temp sensor — voltage high (SPN 3031 FMI 3) · Aftertreatment & Emissions
• Upstream NOx sensor — internal failure reported (SPN 3216 FMI 12) · Aftertreatment & Emissions
• SCR inlet NOx sensor — erratic (SPN 3216 FMI 2) · Aftertreatment & Emissions

All Aftertreatment & Emissions codes

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