LEMON Manuals: Even more car manuals for everyone
Home >> Subaru >> 2020 >> Crosstrek Base, Automatic CVT Trans >> Repair and Diagnosis >> External Pages >> Different variant/trim >> Section 24 (Engine Control System (Diagnostics) (HEV) (2 Of 4)) >> Diagnostic Procedure with Diagnostic Trouble Code (DTC) >> DTC P040C: EGR Temperature Sensor "A" Circuit Low >> Notes

DTC P040C: EGR Temperature Sensor "A" Circuit Low: Notes

WARNING: This page is about a different variant/trim than selected.
  1. DTC detecting condition: 

    Immediately at fault recognition

    Wiring diagram: 

    Engine Electrical System Ref. to WIRING SYSTEM (CROSSTREK MODEL (HEV))>ENGINE ELECTRICAL SYSTEM .

G13237433Courtesy of SUBARU OF AMERICA, INC.
CAUTION: Use the check board when measuring the ECM terminal voltage and resistance. Ref. to ENGINE (DIAGNOSTICS) (H4DO (HEV))>GENERAL DESCRIPTION>PREPARATION TOOL>HOW TO USE CHECK BOARD .
NOTE: After the faulty parts are repaired or replaced, perform the final check in Basic Diagnostic Procedure. Ref. to ENGINE (DIAGNOSTICS) (H4DO (HEV))>BASIC DIAGNOSTIC PROCEDURE>PROCEDURE .
G13615308Courtesy of SUBARU OF AMERICA, INC.
  1. CHECK DATA MONITOR  .
    1. Turn the ignition switch to ON.
    2. Using the Subaru Select Monitor, read the value of [Exhaust Gas Recirculation Temperature Sensor A (B1-S1)] of the data monitor.
      NOTE: For detailed operation procedures, refer to "Common (Diagnostics)". Ref. to COMMON (DIAG)>DATA MONITOR .

      Is the value of [Exhaust Gas Recirculation Temperature Sensor A (B1-S1)] 255[°C] (491°F) or more?

      Yes:  Go to  2.

      No:  Even if DTC is detected, the circuit has returned to a normal condition at this time. Reproduce the failure, and then perform the diagnosis again.

      NOTE: In this case, temporary poor contact of connector, temporary short circuit of harness may be the cause.
  2. CHECK HARNESS BETWEEN ECM AND EGR TEMPERATURE SENSOR CONNECTOR (SHORT TO GROUND)  .
    1. Turn the ignition switch to OFF.
    2. Disconnect the connector from ECM.
    3. Disconnect the connector from EGR temperature sensor.
    4. Measure the resistance between the ECM connector and engine ground.

      Connector & terminal 

      (E158) No. 31 - Engine ground:

      Is the resistance 1 MΩ or more?

      Yes:  Replace the EGR temperature sensor. Ref. to EMISSION CONTROL (AUX. EMISSION CONTROL DEVICES) (H4DO (HEV))>EGR TEMPERATURE SENSOR .

      No:  Repair the short circuit to ground in harness between ECM connector and EGR temperature sensor connector.