CCV Filter Restriction High
What does DD-520194-31 mean?
The DD-520194-31 (Detroit Diesel DD Series) diesel fault code means: CCV Filter Restriction High. This is a moderate severity code.
Common Symptoms
- Check Engine Light / Amber Warning Lamp illuminated
- Oil leaks from seals / dipstick pushout
Probable Causes (Ranked by Likelihood)
- Plugged crankcase ventilation filter (CCV) Very Likely
Step-by-Step Diagnostic Procedure
Replace CCV filter — service interval every ~150K miles.
Clear code and monitor crankcase pressure.
Frequently Asked Questions
What is Detroit Diesel fault code DD-520194-31?
Detroit Diesel fault DD-520194-31 (SPN 520194 FMI 31) indicates: CCV Filter Restriction High. It is a moderate-severity fault and is commonly seen on DD13/DD15/DD16 engines in Freightliner and Western Star chassis.
Can I drive my Freightliner or Western Star with fault DD-520194-31?
It depends on severity. Critical and serious faults trigger derate or engine shutdown — do not continue driving. Moderate faults usually allow continued operation short-term but schedule repair to prevent cascading aftertreatment damage.
How much does it cost to fix Detroit Diesel fault DD-520194-31?
Typical repair cost is $500-$2,200. Sensor/harness fixes fall at the low end; turbo actuator, injector, aftertreatment component, or head gasket repairs fall at the high end. Detroit DDDL software and sometimes factory parameter reset are required for proper reset.