What causes a P1407 code?

P1407 can be triggered by several issues — see the verified probable causes and step-by-step diagnostics shared by mechanics and owners on OBDIY.

Can I drive with a P1407 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P1407 active.

Follow the step-by-step diagnostic on this page, then read the verified fixes contributed by other Heavy Truck owners — the answer marked "Verified Cause" worked for the original poster.

OBDIY

OBD-II

P1407

CCVCD leakage fault

What it means

Crankcase Ventilation Check Device (CCVCD) Leakage Fault. The engine ECM has detected that the crankcase pressure is not within expected parameters, suggesting a leak in the closed crankcase ventilation system.