What causes a SPN 466 code?

SPN 466 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 SPN 466 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with SPN 466 active.

How do I fix SPN 466?

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

J1939 SPN

SPN 466

J1939 SPN 466 — Fuel/Air parameter

What it means

SPN 466 indicates a circuit fault (short to ground, short to high, or open circuit) within the Fuel Heater system, which is used to prevent paraffin wax buildup in diesel fuel during cold temperatures.