AUTOMATIC TRANSAXLE SYSTEM, Diagnostic DTC:P0766

DTC Code DTC Name
P0766 Shift Solenoid "D" Performance (Shift Solenoid Valve S4)

SYSTEM DESCRIPTION

The ECM uses signals from the vehicle speed sensor to detect the actual gear position (1st, 2nd, 3rd or 4th (O/D) gear).

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

DTC No. DTC Detection Condition Trouble Area
P0766 The gear required by the ECM does not match the actual gear when driving (2-trip detection logic)

  • Shift solenoid valve S4 remains open or closed

  • Valve body is blocked

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

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 (O/D) gear position). 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

Tech Tips

Using the Intelligent tester to perform Active Test allows relays, VSVs, actuators and other items to be operated without removing any parts. This non-intrusive functional inspection can be very useful because intermittent operation may be discovered before parts or wiring is disturbed. Performing Active Test early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Test.


  1. PERFORM ACTIVE TEST


    1. Warm up the engine.

    2. Turn the ignition switch off.

    3. Connect the Intelligent tester to the DLC3.

    4. Turn the ignition switch to ON.

    5. Turn on the Intelligent tester.

    6. Select the item "Enter / Powertrain / Engine and ECT / Active Test / Shift Status".

    7. According to the display on the tester, perform the "Active Test".

      Tech Tips

      While driving, the shift position can be forcibly changed with the Intelligent tester.

      Comparing the shift position commanded by the Active Test with the actual shift position enables you to confirm the problem Click here.

      Engine and ECT
      Tester Display Test Part Control Range Diagnostic Note
      Control the Shift Position

      [Test Details]

      Operate the shift solenoid valve and set each shift position by yourself.

      [Vehicle Condition]


      • IDL: ON

      • Less than 50 km/h (31 mph)

      [Others]


      • Press "→" button: Shift up

      • Press "←" button: Shift down

      		 1st / 2nd / 3rd / 4th Possible to check the operation of the shift solenoid valves.

      Tech Tips


      • This test can be conducted when the vehicle speed is 50 km/h (31 mph) or less.

      • The shift position commanded by the ECM is shown in the Data List / Shift Status display on the Intelligent tester.

PROCEDURE


  1. CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P0766)


    1. Connect the Intelligent tester to the DLC3.

    2. Turn the ignition switch to ON and turn the Intelligent tester main switch on.

    3. Select the item "Enter / Powertrain / Engine and ECT / Trouble Codes".

    4. Read the DTCs using the Intelligent tester.

      Result
      Display (DTC output) Proceed to
      Only "P0766" is output A
      "P0766" and other DTCs B

      Tech Tips

      If any other codes besides "P0766" are output, perform the troubleshooting for those DTCs first.


    B

    GO TO DTC CHART Click here

    A

  2. INSPECT SHIFT SOLENOID VALVE S4


    1. A01ET32E02
      Text in Illustration
      *1 Shift Solenoid Valve S4

      Remove the shift solenoid valve S4.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Solenoid Connector (S4) - Solenoid Body (S4) 20°C (68°F) 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 S4 Click here

    OK

  3. INSPECT TRANSMISSION VALVE BODY ASSEMBLY


    1. Check the transmission valve body assembly Click here.

      OK
      There are no foreign objects on each valve.

    NG

    REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY Click here

    OK

  4. INSPECT TORQUE CONVERTER ASSEMBLY


    1. Check the torque converter assembly Click here.

      OK
      The torque converter assembly operates normally.

    NG

    REPLACE TORQUE CONVERTER ASSEMBLY Click here

    OK

    REPAIR OR REPLACE AUTOMATIC TRANSAXLE ASSEMBLY Click here