AUTOMATIC TRANSMISSION SYSTEM, Diagnostic DTC:P0973, P0974

DTC Code DTC Name
P0973 Shift Solenoid "A" Control Circuit Low (Shift Solenoid Valve S1)
P0974 Shift Solenoid "A" Control Circuit High (Shift Solenoid Valve S1)

DESCRIPTION

Shifting from 1st to 6th is performed in combination with "ON" and "OFF" operation of the shift solenoid valves SL1, SL2, S1, S2, S3, S4 and SR which is controlled by the ECM. If an open or short circuit occurs in either of the shift solenoid valves, the ECM controls the remaining normal shift solenoid valve to allow the vehicle to be operated smoothly. (In case of an open or short circuit, the ECM stops sending current to the circuit.) Fail safe function Click here.

DTC No. DTC Detection Condition Trouble Area
P0973 ECM detects short in solenoid valve S1 circuit 2 times when solenoid valve S1 is operated (1-trip detection logic)

  • Short in shift solenoid valve S1 circuit

  • Shift solenoid valve S1

  • ECM
P0974 ECM detects open in solenoid valve S1 circuit 2 times when solenoid valve S1 is not operated (1-trip detection logic)

  • Open in shift solenoid valve S1 circuit

  • Shift solenoid valve S1

  • ECM

MONITOR DESCRIPTION

These DTCs indicate an open or short in the shift solenoid valve S1 circuit. When there is an open or short circuit in any shift solenoid valve circuit, the ECM detects the problem and illuminates the MIL and stores the DTC. When the shift solenoid valve S1 is on, if resistance is 8 Ω or less, the ECM determines there is a short in the shift solenoid valve S1 circuit.

When the shift solenoid valve S1 is off, if resistance is 100 kΩ or more, the ECM determines there is an open in the shift solenoid valve S1 circuit Click here.

WIRING DIAGRAM

A01FE2SE01

INSPECTION PROCEDURE

Tech Tips

The shift solenoid valve S1 is turned on/off normally when the shift lever is in the D position:

ECM command gearshift 1st 2nd 3rd 4th 5th 6th
Shift solenoid valve S1 OFF ON ON ON ON ON

PROCEDURE


  1. INSPECT TRANSMISSION WIRE (S1)


    1. A01FEYSE44
      Text in Illustration
      *1

      Component without harness connected

      (Transmission Wire)

      Disconnect the transmission wire connector from the transmission.

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

      Standard resistance
      Tester Connection

      Specified Condition

      20°C (68°F)
      8 (S1) - Body ground 11 to 15 Ω

    NG

    Click here

    OK

  2. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - ECM)


    1. A01FIKXE04
      Text in Illustration
      *1

      Rear view of wire harness connector

      (to ECM)

      Connect the transmission connector to the transmission.

    2. Disconnect the connector from the ECM.

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

      Standard resistance
      Tester Connection

      Specified Condition

      20°C (68°F)
      F1-5 (S1) - Body ground 11 to 15 Ω

    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

    REPLACE ECM Click here

  3. INSPECT SHIFT SOLENOID VALVE S1


    1. A01FDJME01
      Text in Illustration
      *1 Shift Solenoid Valve S1

      Remove the shift solenoid valve S1.

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

      Standard resistance
      Tester Connection

      Specified Condition

      20°C (68°F)
      Solenoid Connector (S1) - Solenoid Body (S1) 11 to 15 Ω

    3. Connect the positive (+) lead to the terminal of the solenoid connector, and the negative (-) lead to the solenoid body.

      OK
      The solenoid makes an operating sound.

    NG

    REPLACE SHIFT SOLENOID VALVE S1 Click here

    OK

    REPAIR OR REPLACE TRANSMISSION WIRE Click here