ECD SYSTEM, Diagnostic DTC:12

DTC Code DTC Name
12 Crankshaft Position Sensor Circuit Malfunction

DESCRIPTION

The crankshaft position sensor in the engine control system contains a signal plate and a pickup coil for the TDC signal. The TDC signal plate has 1 tooth on its outer circumference. The TDC signal sensor generates 1 signal for every crankshaft revolution. The ECM detects the top dead center position based on the TDC signal.

DTC Code DTC Detection Condition Trouble Area
12 No TDC signal is sent to the ECM at 400 rpm or more.

  • Open or short in crankshaft position sensor circuit

  • Crankshaft position sensor

  • ECM

WIRING DIAGRAM

A01DQHFE01

INSPECTION PROCEDURE

PROCEDURE


  1. INSPECT CRANKSHAFT POSITION SENSOR


    1. Inspect the crankshaft position sensor Click here.


    NG

    REPLACE CRANKSHAFT POSITION SENSOR Click here

    OK

  2. CHECK ECM (TDC, NE SIGNAL)


    1. A01DQW6E09
      Text in Illustration
      *a

      Component with harness connected

      (ECM)
      *b TDC and NE Signal Waveforms

      While cranking or idling, check the waveforms according to the value(s) in the table below.

      OK
      Tester Connection Condition Specified Condition
      C101-17 (TDC+) - C101-16 (TDC-) Idling Correct waveform is as shown
      C101-19 (NE+) - C101-18 (NE-) Idling Correct waveform is as shown

    NG

    CHECK HARNESS AND CONNECTOR (ECM - CRANKSHAFT POSITION SENSOR) Click here

    OK

    REPLACE ECM Click here

  3. CHECK HARNESS AND CONNECTOR (ECM - CRANKSHAFT POSITION SENSOR)


    1. Disconnect the crankshaft position sensor connector.

    2. Disconnect the ECM connector.

    3. Measure the resistance according to the value(s) in the table below.

      Standard Resistance (Check for Open)
      Tester Connection Condition Specified Condition
      C109-1 - C101-17 (TDC+) Always Below 1 Ω
      C109-2 - C101-16 (TDC-) Always Below 1 Ω
      Standard Resistance (Check for Short)
      Tester Connection Condition Specified Condition
      C109-1 or C101-17 (TDC+) - Body ground Always 10 kΩ or higher
      C109-2 or C101-16 (TDC-) - Body ground Always 10 kΩ or higher

    4. Reconnect the crankshaft position sensor connector.

    5. Reconnect the ECM connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    CHECK FOR INTERMITTENT PROBLEMS Click here