Detailed guide for SPN 523497 FMI 31
Back to top ↑DOC performance issues show up as regen inefficiency.\n\nBefore blaming the DOC, confirm sensors and check for exhaust leaks that bleed heat.
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Share ↓SPN 523497 FMI 31Severity: Warning
SPN 523497 FMI 31: Aftertreatment diesel oxidation catalyst (DOC) performance condition exists
Quick Answer
Aftertreatment diesel oxidation catalyst (DOC) performance condition exists
Code
SPN 523497 FMI 31
Severity
Warning
Applies to
Check OEM application
Can I drive?
Driving suitability is not established by this code alone.
Common Symptoms
- Regens not working efficiently
- Soot load rising faster than normal
- May cause repeated aftertreatment faults
Likely Causes
- DOC aging/contamination
- Exhaust leaks affecting temps
- Frequent low-temp operation
Common Fixes
- Check for leaks and sensor accuracy
- Review regen history and exhaust temps
- Service aftertreatment if confirmed
Full technical sections↓
What does SPN 523497 FMI 31 mean?
Back to top ↑Aftertreatment diesel oxidation catalyst (DOC) performance condition exists
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