AUTOMATIC TRANSMISSION SYSTEM, 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. Detection Item DTC Detection Condition Trouble Area MIL Memory
P0746 Pressure Control Solenoid "A" Performance (Shift Solenoid Valve SL1)

All of the following conditions are met (2 trip detection logic)


  1. Engine coolant temperature is 40°C (104°F) or more

  2. ATF temperature is -10°C (14°F) or more

  3. The vehicle is driven with the shift lever in D

  4. No malfunctions are detected in shift solenoid valve SL1, 2, 3, 4 and 5, SR, transmission revolution sensors (NT, NC3, SP2), oil pressure switch, water temperature sensor, oil temperature sensor, knock control sensor, electronic throttle, or CAN

  5. Either of the following conditions (a) or (b) is met


    1. When gear shifts to 6th, 7th, and 8th are requested by the TCM, the oil pressure switch is ON, and this status is detected 2 times per trip.

    2. When gear shifts to 1st to 5th are requested by the TCM, the engine speed overruns (neutral status) for 0.5 seconds or more continuously.

DTC Detection Condition 1, 2, 3, 4 and 5 (a):


  • Shift solenoid valve SL1

  • Oil pressure switch

  • Valve body assembly

  • Automatic transmission assembly

DTC Detection Condition 1, 2, 3, 4 and 5 (b):


  • Shift solenoid valve SL1

  • Shift solenoid valve SLT

  • Valve body assembly

  • Automatic transmission assembly

 Comes on DTC stored
DTC Detection Condition Patterns:
Vehicle Condition
Pattern 1 Pattern 2
Diagnostic Condition Engine coolant temperature is 40°C (104°F) or more ○ ○
ATF temperature is -10°C (14°F) or more ○ ○
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, water temperature sensor, oil temperature sensor, knock control sensor, electronic throttle, or CAN. ○ ○
Malfunction Condition When gear shifts to 6th, 7th, and 8th are requested by the TCM, the oil pressure switch is ON ○ -
When gear shifts to 1st to 5th are requested by the TCM, the engine speed overruns (neutral status). - ○
Duration 2 times 0.5 seconds or more
Detection Logic 2 trip detection logic 2 trip detection logic

Tech Tips

This DTC is output when either of the above detection patterns is met.

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 store this DTC.

CAUTION / NOTICE / HINT

Note

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

Click here

Tech Tips

After the repair, clear the DTCs and perform the following procedure to check that DTCs are not output.


  1. Perform the D Position Shift Test in Road Test.

    Click here

  2. Turn the engine switch off.

  3. Perform step (1) again.

  4. Check for DTCs again.

    Click here

PROCEDURE


  1. CHECK DTC OUTPUT


    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.


      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.

      Tech Tips

      Write down the currently output DTCs before clearing them.


      Powertrain > ECT > Clear DTCs

    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. B002E4SC46
      *a

      Component without harness connected

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

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

    OK

    GO TO STEP 5 Click here

    NG

    REPLACE SHIFT SOLENOID VALVE SL1 Click here

  4. INSPECT SHIFT SOLENOID VALVE SLT


    1. B002E4SC46
      *a

      Component without harness connected

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

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

    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.
      Result
      Proceed to
      OK
      NG

    OK

    REPAIR OR REPLACE AUTOMATIC TRANSMISSION ASSEMBLY Click here

    NG

    REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY Click here