U1000 Code: Meaning, Causes, and Symptoms | OBD2 Codes

U1000 – Invalid or Missing Data for Primary Id


U1000 Possible Symptoms


Engine Light ON (or Service Engine Soon Warning Light)


U1000 Possible Causes


Controller Area Network (CAN) communication harness is open or shorted,Faulty Engine Control Module (ECM),Poor harness ground connection.


U1000 Description


CAN (Controller Area Network) is a serial communication line for real time application. It is an on-vehicle multiplex communication line with high data communication speed and excellent error detection ability. Many electronic control units are equipped onto a vehicle, and each control unit shares information and links with other control units during operation (not independent). In CAN communication, control units are connected with 2 communication lines (CAN H line, CAN L line) allowing a high rate of information transmission with less wiring. Each control unit transmits/receives data but selectively reads required data only.