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

Based upon a signal from the TCM, the combination of shift solenoid valve (S1, S2, S3, S4, SR, SL1, SL2) changes the gear position from 1st to 6th. As a fail-safe function if the solenoid valve system is open or shorted, the TCM cuts power to all solenoids, leaving just the mechanical hydraulic circuit, requiring manual shifting.

DTC No.

DTC Detection Condition


  1. Diagnosis Condition

  2. Malfunction Status

  3. Malfunction Time

  4. Other

 Trouble Area
P0973

  1. Not learning control prohibited status

  2. During shift solenoid valve S1 on signal is output, the TCM S1 output monitor value is "off".

  3. Continues for 500ms or more.

  4. 1-trip detection logic

  • Shift solenoid valve S1

  • Transmission wire

  • Harness and connector

  • TCM
P0974

  1. Not learning control prohibited status

  2. During shift solenoid valve S1 off signal is output, the TCM S1 output monitor value is "on".

  3. Continues for 500ms or more.

  4. 1-trip detection logic

  • Shift solenoid valve S1

  • Transmission wire

  • Harness and connector

  • TCM

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 TCM detects the problem and illuminates the MIL and stores the DTC.

WIRING DIAGRAM

A004J76E01
*a Shift Solenoid Valve S1
*b Transmission Wire

CAUTION / NOTICE / HINT

Note

Perform the universal trip to clear permanent DTCs Click here.

Tech Tips

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

TCM 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. Disconnect the A18 TCM connector.

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

      Standard voltage
      Tester Connection Condition Specified Condition
      A18-7(S1) - Body ground Ignition switch ON Below 1 V

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

      Standard resistance
      Tester Connection Condition Specified Condition
      A18-7(S1) - Body ground 20°C(68°F) 11 to 15 Ω

    4. Connect the A18 TCM connector.


    NG

    CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - TCM) Click here

    OK

  2. REPLACE TCM


    1. Replace the TCM Click here.


    NEXT

    PERFORM THE RESET MEMORY Click here

  3. CHECK HARNESS AND CONNECTOR (TRANSMISSION WIRE - TCM)


    1. Disconnect the A18 TCM connector.

    2. Disconnect the L4 transmission wire connector.

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

      Standard voltage
      Tester Connection Condition Specified Condition
      L4-1(S1) - Body ground Ignition switch ON Below 1 V

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

      Standard resistance
      Tester Connection Condition Specified Condition
      L4-1(S1) - A18-7(S1) Always Below 1 Ω
      L4-1(S1) and A18-7(S1) - Body ground Always 10 kΩ or higher

    5. Connect the A18 TCM connector.

    6. Connect the L4 transmission wire connector.


    NG

    REPAIR OR REPLACE HARNESS OR CONNECTOR

    OK

  4. INSPECT SHIFT SOLENOID VALVE S1


    1. Remove the shift solenoid valve S1 Click here.

    2. Perform inspection of the shift solenoid valve S1 Click here.


    OK

    REPAIR OR REPLACE TRANSMISSION WIRE Click here

    NG

    REPLACE SHIFT SOLENOID VALVE S1 Click here