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DTC C1201/51 Engine Control System Malfunction: Description

If a malfunction in the engine control system is detected, the operations of VSC and TRAC are prohibited by the fail-safe function. When the signals from the engine are input normally, the fail-safe is cancelled and the DTC is not stored.

DTC DETECTION CONDITION

DTC No. DTC Detecting Condition Trouble Area
C1201/51  Engine control system malfunction signal continues for 5 seconds. Engine control system
  1. CHECK HARNESS AND CONNECTOR (MOMENTARY INTERRUPTION) 
    1. Using the intelligent tester, check for any momentary interruption in the wire harness and connector corresponding to a DTC (See HOW TO PROCEED WITH TROUBLESHOOTING  ).

      DATA LIST: ABS/VSC 

      DATA LIST - ABS/VSC

      Item Measurement Item / Range (Display) Normal Condition
      EFI COM OPN EFI communication open detection / ERROR or NORMAL ERROR: Momentary interruption
      NORMAL: Normal

      OK: 

      There are no momentary interruptions. 

      HINT:

      Perform the above inspection before removing the sensor and connector.

      NG : Go to step   3 

      OK : Go to next step 

  2. CHECK DTC FOR ENGINE CONTROL SYSTEM 
    1. Clear the DTC (engine control system) (See DTC CHECK / CLEAR ).
    2. Check the DTC (engine control system) (See DTC CHECK / CLEAR ).

      Result 

      RESULT REFERENCE

      Display (DTC Output) Proceed To
      DTC (engine control system) is not output A
      DTC (engine control system) is output B (See DATA LIST / ACTIVE TEST )

      NG : REPAIR ENGINE CONTROL SYSTEM ACCORDING TO DTC OUTPUT 

      A : REPLACE ECM 

  3. REPAIR OR REPLACE HARNESS OR CONNECTOR (ECM TO SKID CONTROL ECU) 

    NEXT 

  4. RECONFIRM DTC 
    1. Clear the DTC (See DTC CHECK / CLEAR  ).
    2. Perform a road test.
    3. Check that the same DTC is recorded (See DTC CHECK / CLEAR  ).

      Result 

      RESULT REFERENCE

      Display (DTC Output) Proceed To
      DTC (C1201/51) is not output A
      DTC (C1201/51) is output B

      B : Go to step   2 

      A : END