AUTOMATIC TRANSMISSION SYSTEM, Diagnostic DTC:P0751

DTC Code DTC Name
P0751 Shift Solenoid "A" Performance (Shift Solenoid Valve S1)

DESCRIPTION

The ECM uses signals from the speed sensor (NC0) and speed sensor (SP2) to detect the actual gear position (1st, 2nd, 3rd or 4th gear).

Then the ECM compares the actual gear position with the shift schedule in the ECM memory to detect mechanical problems of the shift solenoid valves, valve body or automatic transmission (clutch, brake or gear etc.).

DTC Code DTC Detection Condition Trouble Area
P0751 Gear required by ECM does not match actual gear when driving (2 trip detection logic)

  • Shift solenoid valve S1 remains open or closed

  • Valve body is blocked

  • Shift solenoid valve S1

  • Automatic transmission (clutch, brake or gear etc.)

  • ECM

MONITOR DESCRIPTION

The ECM commands gear shifts by turning the shift solenoid valves "on/off". According to the input shaft revolution, intermediate (counter) shaft revolution and output shaft revolution, the ECM detects the actual gear position (1st, 2nd, 3rd or 4th gear). When the gear position commanded by the ECM and the actual gear position are not the same, the ECM illuminates the MIL and stores the DTC.

INSPECTION PROCEDURE

PROCEDURE


  1. CHECK DTC OUTPUT (IN ADDITION TO DTC P0751)


    1. Connect the intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and push the intelligent tester main switch on.

    3. Enter the following menus: Powertrain / ECT / DTC / Current or Pending.

    4. Read the DTCs using the intelligent tester.

      Result
      Display (DTC output) Proceed to
      Only P0751 is output A
      P0751 and other DTCs are output B

      Tech Tips

      If any other codes besides P0751 are output, perform troubleshooting for those DTCs first.


    B

    GO TO DTC CHART

    A

  2. INSPECT SHIFT SOLENOID VALVE S1


    1. A01E1OTE02

      Remove the shift solenoid valve S1.

    2. Measure the resistance of the solenoid value.

      Standard Resistance
      Tester Connection Condition Specified Condition
      Shift solenoid S1 connector - Shift solenoid S1 body 20°C (68°F) 11 to 15 Ω

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

    4. Check the operating noise of the solenoid valve.

      OK
      Solenoid makes operating noise.

    NG

    REPLACE SHIFT SOLENOID VALVE S1

    OK

  3. INSPECT TRANSMISSION VALVE BODY ASSEMBLY


    1. Check the transmission valve body assembly.

      OK
      There are no foreign objects on any valve.

    NG

    REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY

    OK

    REPAIR OR REPLACE AUTOMATIC TRANSMISSION ASSEMBLY