What causes a P0561 code?

P0561 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 P0561 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with P0561 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

P0561

System Voltage Unstable and Imprecise

What it means

The Engine Control Module (ECM) detects intermittent or unstable voltage signals that do not align with expected battery or alternator charging parameters.