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Home >> Nissan-Datsun >> 2008 >> Altima Base >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 17 (Engine Control System (Hybrid)) >> Component Diagnosis >> U0400, U1021 Can Comm Data >> DTC Logic >> DTC Detection Logic
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DTC Detection Logic

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DTC DETECTING CONDITION AND POSSIBLE CAUSE

DTC No. Trouble diagnosis name DTC detecting condition Possible cause
U0400 Invalid data received from hybrid vehicle control ECU SUM data on CAN signal of OBD (emission related diagnosis) from HV ECU is different from SUM data calculated by ECM.
  • Harness or connectors

    (HEV SYSTEM CAN communication line is open or shorted)

  • ECM
  • HV ECU
U1021 SUM data on CAN signal other than OBD (emission related diagnosis) from HV ECU is different from SUM data calculated by ECM.