What causes a P1873 code?

P1873 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 P1873 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P1873 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

P1873

Turbocharger compressor temperature sensor out of range low

What it means

The ECM detects that the Compressor Inlet Temperature (CIT) sensor voltage is below the minimum calibrated threshold, typically indicating a short to ground or a failed sensor.