AUTOMATIC TRANSMISSION SYSTEM, Diagnostic DTC:P0979, P0980

DTC Code DTC Name
P0979 Shift Solenoid "C" Control Circuit Low (Shift Solenoid Valve S3)
P0980 Shift Solenoid "C" Control Circuit High (Shift Solenoid Valve S3)

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
P0979

  1. Not learning control prohibited status

  2. During shift solenoid valve S3 on signal is output, the TCM's S3 output monitor value is "off".

  3. Continues for 500ms or more.

  4. 1-trip detection logic

  • Shift solenoid valve S3

  • Transmission wire

  • Harness and connector

  • TCM
P0980

  1. Not learning control prohibited status

  2. During shift solenoid valve S3 off signal is output, the TCM's S3 output monitor value is "on".

  3. Continues for 500ms or more.

  4. 1-trip detection logic

  • Open in shift solenoid valve S3 circuit

  • Shift solenoid valve S3

  • TCM

MONITOR DESCRIPTION

These DTCs indicate an open or short in the shift solenoid valve S3 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

A004J76E03
*a Shift Solenoid Valve S3
*b Transmission Wire

CAUTION / NOTICE / HINT

Note

Perform the universal trip to clear permanent DTCs Click here.

Tech Tips


  • The shift solenoid valve S3 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 S3 ON ON ON OFF OFF OFF

PROCEDURE


  1. INSPECT TRANSMISSION WIRE (S3)


    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
      A18-6(S3) - 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
      A18-6(S3) - 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
      L4-2(S3) - 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
      L4-2(S3) - A18-6(S3) Always Below 1 Ω
      L4-2(S3) or A18-6(S3) - 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 S3


    1. Remove the shift solenoid valve S3 Click here.

    2. Perform inspection of the shift solenoid valve S3 Click here.


    OK

    REPAIR OR REPLACE TRANSMISSION WIRE Click here

    NG

    REPLACE SHIFT SOLENOID VALVE S3 Click here