What causes a U3138 code?

U3138 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 U3138 code?

Drivability depends on the severity. Check the severity rating and verified driver reports on this page before continuing to drive with U3138 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

U3138

Manufacturer-specific network code U3138

What it means

Invalid data received from the Blind Spot Detection system. The network detected packets that do not meet expected manufacturer checksums.