C1921

C1921 ENGINE SPEED SIGNAL

Description
^ The engine speed signal is transmitted to 4WAS main control unit via CAN communication.

DTC Logic

C1921:

DTC CONFIRMATION PROCEDURE

1.RECHECK DTC

With CONSULT-III
1. Turn the ignition switch from OFF to ON.
2. Perform 4WAS main control unit self-diagnosis.
Is DTC "C1921" detected?
YES >> Proceed to diagnosis procedure. Refer to "Diagnosis Procedure".
NO >> INSPECTION END

Diagnosis Procedure

1.PERFORM ECM SELF-DIAGNOSIS

With CONSULT-III
Perform ECM self-diagnosis.
Is any error system detected?
YES >> Check the error system.
NO >> GO TO 2.

2.PERFORM SELF-DIAGNOSIS (4WAS MAIN CONTROL UNIT)

With CONSULT-III
Perform 4WAS main control unit self-diagnosis.
Is DTC "U1000" or "U1010" detected?
YES >> Check the error system.
NO >> GO TO 3.

3.PERFORM SELF-DIAGNOSIS (4WAS MAIN CONTROL UNIT)

With CONSULT-III
Perform 4WAS main control unit self-diagnosis.
Is DTC "C1921" detected?
YES >> Replace 4WAS main control unit.
NO >> GO TO 4.

4.INFORMATION CHECK

With CONSULT-III
Check the "DATA MONITOR" value of each DTC detected with the self-diagnosis function. Refer to STC-155, "Reference Value". 4WAS Main Control Unit
Is each data the standard value?
YES >> Check that there is no malfunction in each harness connector pin terminal or disconnection.
NO >> Replace 4WAS main control unit.

Special Repair Requirement

BEFORE REPLACING 4WAS MAIN CONTROL UNIT
^ Record the self-diagnosis results (history).

CAUTION:
^ Never erase the memory (history) of self-diagnosis results when replacing 4WAS main control unit after diagnosis.
^ Erase the memory of the self-diagnosis results (record) after printing out or recording all the values of "DATA MONITOR".