What causes a P0794 code?

P0794 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 P0794 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P0794 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

P0794

Intermediate Shaft Speed Sensor Intermittent Circuit Fault

What it means

The engine or transmission control module has detected an intermittent or erratic signal from the intermediate shaft speed sensor circuit. This sensor measures the rotation speed of the internal shafts between the input and output sensors to manage shift timing.