What causes a U0612 code?

U0612 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 U0612 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with U0612 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

U0612

Network/CAN bus communication code U0612

What it means

Lost communication with Fuel Injector Control Module (FICM) 'B'. Data transfer between the ECM and the second injector bank controller has been interrupted.