What causes a P1729 code?

P1729 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 P1729 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P1729 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

P1729

DPFRM NMD regeneration timeout fault

What it means

DPFRM NMD (Non-Methane Diesel) Regeneration Timeout Fault. This indicates the engine control module attempted to perform a regeneration, but the particulate filter failed to reach the target temperature or cleanliness level within the allowed time frame.