AUTOMATIC TRANSMISSION SYSTEM, Diagnostic DTC:P0746

DTC Code DTC Name
P0746 Pressure Control Solenoid "A" Performance or Stuck OFF

DESCRIPTION

Based on signals from the transmission revolution sensors (NT and SP2), the actual gear is detected.

If the detected gear is different than the commanded gear, the TCM detects related mechanical problems in the shift solenoid valves, transmission valve body assembly and automatic transmission assembly (clutch, brake, gear, etc.).

Tech Tips

Actual gear when a problem occurs in shift solenoid valve SL1 (without fail-safe control):

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* N* N* N* N* 6th 7th 8th

  • *: Neutral

DTC No.

DTC Detection Condition


  1. Diagnosis Condition

  2. Malfunction Status

  3. Malfunction Time

  4. Other

 Trouble Area
P0746

SL1 stuck ON malfunction:


  1. Battery voltage is 9.5 V or higher, engine speed is more than 400 rpm, and the vehicle is driven with the shift lever in D (no malfunctions are detected in shift solenoid valve SC1, SC2, SL1, SL2, SL3, SL4, SL5, SLT, SLU, park/neutral position switch assembly, TCM, electronic throttle, knock control sensor, No. 1 ATF temperature sensor, transmission revolution sensors (NT), and CAN communication system)

  2. The gear commanded by the TCM is the same as the actual gear

  3. Malfunction status is detected 4 times per trip

  4. 2 trip detection logic

  • Shift solenoid valve SC1

  • Shift solenoid valve SL1

  • Transmission valve body assembly

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

SL1 stuck OFF malfunction:


  1. Battery voltage is 9.5 V or higher, engine speed is more than 400 rpm, and the vehicle is driven with the shift lever in D (no malfunctions are detected in shift solenoid valve SC1, SC2, SL1, SL2, SL3, SL4, SL5, SLT, SLU, park/neutral position switch assembly, TCM, electronic throttle, knock control sensor, No. 1 ATF temperature sensor, transmission revolution sensors (NT), and CAN communication system)

  2. When the TCM commands the transmission to shift to 1st to 5th, the engine overruns (neutral status).

  3. Malfunction status is detected 5 times per trip

  4. 2 trip detection logic

  • Shift solenoid valve SL1

  • Shift solenoid valve SL2

  • Shift solenoid valve SL3

  • Shift solenoid valve SL4

  • Shift solenoid valve SL5

  • Shift solenoid valve SLT

  • Transmission valve body assembly

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

MONITOR DESCRIPTION

The TCM commands gear shifts by turning the shift solenoid valves on and off. According to the input shaft speed and output shaft 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.


CAUTION / NOTICE / HINT

Note

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

Tech Tips

After performing 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.*1

  2. Turn the engine switch off.

  3. Perform step (*1) again.

  4. Check for DTCs again Click here.

PROCEDURE


  1. CHECK DTC OUTPUT (IN ADDITION TO DTC P0746)


    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
      DTC P0746 and DTC P076B, P076C, P0776, P0796, P08CD, P08CE, P2714, P2808 and/or P2817 are output A
      Only DTC P0746 is output B
      DTCs other than P0746, P076B, P076C, P0776, P0796, P08CD, P08CE, P2714, P2808 and P2817 are also output C

      Tech Tips

      If DTCs other than P0746, P076B, P076C, P0776, P0796, P08CD, P08CE, P2714, P2808 and P2817 are output, perform troubleshooting for those DTCs first.


    B

    INSPECT SHIFT SOLENOID VALVE SL1, SL2, SL3, SL4 AND SL5 Click here

    C

    GO TO DTC CHART Click here

    A

  2. CLEAR DTC AND PERFORM STALL SPEED TEST


    1. Clear the DTCs Click here.

      Tech Tips

      Write down the currently output DTCs before clearing them.

    2. Perform the stall speed test Click here.

      Result
      Test Condition Proceed to
      Stall speed test can be performed A
      Stall speed test cannot be performed B

    B

    INSPECT SHIFT SOLENOID VALVE SLT Click here

    A

  3. INSPECT SHIFT SOLENOID VALVE SL1, SL2, SL3, SL4 AND SL5


    1. B00201YE13
      Text in Illustration
      *1 Shift Solenoid Valve SL1, SL2, SL3, SL4 and SL5

      Remove the shift solenoid valve SL1, SL2, SL3, SL4 and SL5 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
      Terminal 1 of the shift solenoid valve SL2 - Terminal 2 20°C (68°F) 5.0 to 5.6 Ω
      Terminal 1 of the shift solenoid valve SL3 - Terminal 2 20°C (68°F) 5.0 to 5.6 Ω
      Terminal 1 of the shift solenoid valve SL4 - Terminal 2 20°C (68°F) 5.0 to 5.6 Ω
      Terminal 1 of the shift solenoid valve SL5 - Terminal 2 20°C (68°F) 5.0 to 5.6 Ω

    3. Apply 12 V battery voltage to the shift solenoid valve and check that the valve moves and makes an operating noise.

      OK
      Measurement Condition Specified Condition

      • Battery positive (+) with a 21 W bulb → Terminal 2

      • Battery negative (-) → Terminal 1

      		 Valve moves and makes an operating noise

    NG

    REPLACE SHIFT SOLENOID VALVE SL1, SL2, SL3, SL4 OR SL5 Click here

    OK

  4. INSPECT SHIFT SOLENOID VALVE SC1


    1. B001ZECE01
      Text in Illustration
      *1 Shift Solenoid Valve SC1

      Remove the shift solenoid valve SC1 Click here.

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

      Standard Resistance
      Tester Connection Condition Specified Condition
      Shift solenoid valve SC1 connector - Shift solenoid valve SC1 body 20°C (68°F) 11 to 15 Ω

    3. Apply 12 V battery voltage to the shift solenoid valve and check that the valve moves and makes an operating noise.

      OK
      Measurement Condition Specified Condition

      • Battery positive (+) → Shift solenoid valve SC1 connector

      • Battery negative (-) → Shift solenoid valve SC1 body

      		 Valve moves and makes an operating noise

    NG

    REPLACE SHIFT SOLENOID VALVE SC1 Click here

    OK

  5. INSPECT SHIFT SOLENOID VALVE SLT


    1. B00201YE13
      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. Apply 12 V battery voltage to the shift solenoid valve and check that the valve moves and makes an operating noise.

      OK
      Measurement Condition Specified Condition

      • Battery positive (+) with a 21 W bulb → Terminal 2

      • Battery negative (-) → Terminal 1

      		 Valve moves and makes an operating noise

    NG

    REPLACE SHIFT SOLENOID VALVE SLT Click here

    OK

  6. 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.

    OK

    REPAIR OR REPLACE AUTOMATIC TRANSMISSION ASSEMBLY Click here

    NG

    REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY Click here