What causes a P156E code?

P156E 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 P156E code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P156E 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

P156E

Tachometer PWM driver short circuit low

What it means

The ECM has detected a short to ground on the Pulse Width Modulation (PWM) signal circuit used to drive the tachometer on the dashboard.