СИСТЕМА АВТОМАТИЧЕСКОЙ ТРАНСМИССИИ, Diagnostic DTC:P0746

DTC Code DTC Name
P0746 Pressure Control Solenoid "A" Performance (Shift Solenoid Valve SL1)

DESCRIPTION

The TCM detects the actual gear based on signals from the transmission revolution sensors (SP2, NC3 and NT).

Based on the detected gear and oil pressure switch output, the TCM detects related mechanical problems in the shift solenoid valves, valve body and automatic transmission.

Tech Tips

Actual gear when a problem occurs in shift solenoid valve SL1:

TCM commanded gear 1st 2nd 3rd 4th 5th 6th 7th 8th
Actual gear during SL1 stuck ON malfunction 1st 2nd 3rd 4th 5th 6th 7th 8th
Actual gear during SL1 stuck OFF malfunction N*1 N*1 N*1 N*1 N*1 6th 7th 8th

  • *1: Neutral

DTC No.

DTC Detection Condition


  1. Diagnosis Condition

  2. Malfunction Status

  3. Malfunction Time

  4. Other

 Trouble Area
P0746

  1. ECT is 40°C (104°F) or higher, ATF temperature is -10°C (14°F) or higher, and the vehicle is driven with the shift lever in D (no malfunctions are detected in shift solenoid valve SL1, 2, 3, 4 and 5, SR, transmission revolution sensors (NT, NC3, SP2), oil pressure switch, engine coolant temperature sensor, oil temperature sensor, knock control sensor, electronic throttle, or CAN2)

  2. When a gear shift to 6th, 7th, or 8th is requested by the TCM, the oil pressure switch is ON

  3. Malfunction status is detected 2 times per trip

  4. 2 trip detection logic

  • Shift solenoid valve SL1

  • Oil pressure switch

  • Valve body assembly

  • Automatic transmission assembly
P0746

  1. ECT is 40°C (104°F) or higher, ATF temperature is -10°C (14°F) or higher, and the vehicle is driven with the shift lever in D (no malfunctions are detected in shift solenoid valve SL1, 2, 3, 4 and 5, SR, transmission revolution sensors (NT, NC3, SP2), oil pressure switch, engine coolant temperature sensor, oil temperature sensor, knock control sensor, electronic throttle, or CAN2)

  2. When a gear shifts to 1st to 5th are requested by the TCM, the engine speed overruns (neutral status)

  3. Malfunction status continues for 0.5 sec. or more

  4. 2 trip detection logic

  • Shift solenoid valve SL1

  • Shift solenoid valve SLT

  • Valve body assembly

  • Automatic transmission assembly

MONITOR DESCRIPTION

The TCM commands gear shifts by turning the shift solenoid valves on and off. According to the input shaft revolution (speed), intermediate (counter) shaft revolution (speed) and output shaft revolution (speed), the TCM detects the actual gear (1st, 2nd, 3rd, 4th, 5th, 6th, 7th or 8th gear position). When the gear commanded by the TCM and the actual gear are not the same, the TCM illuminates the MIL and stores this DTC.

INSPECTION PROCEDURE

Note

Perform registration and/or initialization when parts related to the automatic transmission are replaced Click here.

PROCEDURE


  1. CHECK DTC OUTPUT (IN ADDITION TO DTC P0746, P0873 AND P2714)


    1. Connect the GTS to the DLC3.

    2. Turn the engine switch on (IG).

    3. Turn the GTS on.

    4. Enter the following menus: Powertrain / ECT / Trouble Codes.

    5. Read the DTCs using the GTS.

      Result
      Result Proceed to
      Only DTCs P0746 and P2714 are output A
      Only DTCs P0746 and P0873 are output B
      P0746, P0873, P2714 and other DTCs are output C

      Tech Tips

      If DTCs other than P0746, P0873 and P2714 are output, perform troubleshooting for those DTCs first.


    B

    GO TO DTC P0873 FLOWCHART Click here

    C

    GO TO DTC CHART Click here

    A

  2. CLEAR THE DTC AND RUNNING TEST


    1. Clear the DTCs Click here.

      Tech Tips

      Write down the currently output DTCs before clearing them.

    2. Start the engine, drive at a low vehicle speed and perform the inspection.

      Result
      Result Proceed to
      Vehicle cannot be driven (vehicle changes to neutral) A
      Vehicle can be driven (vehicle creep occurs) B

    B

    INSPECT SHIFT SOLENOID VALVE SLT Click here

    A

  3. INSPECT SHIFT SOLENOID VALVE SL1


    1. A01FI7WE21
      Text in Illustration
      *1 Shift Solenoid Valve SL1

      Remove the shift solenoid valve SL1 Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Terminal 1 of the shift solenoid valve SL1 - Terminal 2 20°C (68°F) 5.0 to 5.6 Ω

    3. Connect a positive (+) battery lead with a 21 W bulb to terminal 2 and a negative (-) battery lead to terminal 1 of the solenoid valve connector. Then check that the valve moves and makes an operating sound.

      OK
      Valve moves and makes an operating sound.
      Result
      Result Proceed to
      NG A
      OK B

    B

    INSPECT TRANSMISSION VALVE BODY ASSEMBLY Click here

    A

    REPLACE SHIFT SOLENOID VALVE SL1 Click here

  4. INSPECT SHIFT SOLENOID VALVE SLT


    1. A01FI7WE21
      Text in Illustration
      *1 Shift Solenoid Valve SLT

      Remove the shift solenoid valve SLT Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Terminal 1 of the shift solenoid valve SLT - Terminal 2 20°C (68°F) 5.0 to 5.6 Ω

    3. Connect a positive (+) battery lead with a 21 W bulb to terminal 2 and a negative (-) battery lead to terminal 1 of the solenoid valve connector. Then check that the valve moves and makes an operating sound.

      OK
      Valve moves and makes an operating sound.

    NG

    REPLACE SHIFT SOLENOID VALVE SLT Click here

    OK

  5. INSPECT TRANSMISSION VALVE BODY ASSEMBLY


    1. Check the transmission valve body assembly Click here.

      OK
      There is no foreign matter on each valve and they operate smoothly.

    NG

    REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY Click here

    OK

    REPAIR OR REPLACE AUTOMATIC TRANSMISSION ASSEMBLY Click here