U1039 — SCP (J1850) Invalid or Missing Data for Primary Id / Vehicle Speed

What it means

U1039 is an OBD-II diagnostic trouble code: SCP (J1850) Invalid or Missing Data for Primary Id / Vehicle Speed.

Typical fix

Confirm the code with an OBD-II scanner, then inspect the component or circuit named above. Consult a vehicle-specific service manual for the full diagnostic and repair procedure.