Dtc P0751 Shift Solenoid A Performance (Shift Solenoid Valve S1)

Drivetrain. Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25
A750F Automatic Transmission Transaxle. Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25

DESCRIPTION

MONITOR DESCRIPTION

INSPECTION PROCEDURE

CHECK DTC OUTPUT (IN ADDITION TO DTC P0751)

PERFORM ACTIVE TEST USING INTELLIGENT TESTER (SHIFT SOLENOID VALVE SLT)

INSPECT SHIFT SOLENOID VALVE S1

INSPECT TRANSMISSION VALVE BODY ASSEMBLY

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


DESCRIPTION

The TCM uses signals from the output shaft speed sensor and input speed sensor to detect the actual gear position (1st, 2nd, 3rd, 4th or 5th gear).
Then the TCM compares the actual gear with the shift schedule in the TCM memory to detect mechanical problems with the shift solenoid valves, valve body or automatic transmission (clutch, brake, gear, etc.).

DTC Code
DTC Detection Condition
Trouble Area
P0751
Gear required by the TCM does not match the actual gear when driving (2-trip detection logic).
  1. Shift solenoid valve S1 remains open or closed
  2. Shift solenoid valve SLT remains open or closed
  3. Valve body is blocked
  4. Automatic transmission (clutch, brake, gear, etc.)

MONITOR DESCRIPTION

This DTC indicates a stuck ON malfunction or stuck OFF malfunction of shift solenoid valve S1.
The TCM commands gear shifts by turning the shift solenoid valves ON/OFF. When the gear position commanded by the TCM and the actual gear position are not the same, the TCM illuminates the MIL and stores the DTC.

INSPECTION PROCEDURE


ACTIVE TEST
HINT:
Using the intelligent tester to perform Active Tests 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 Tests early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Tests.

  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 the intelligent tester on.

  6. Enter the following menus: Powertrain / ECT / Active Test.

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

    HINT:
    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 (HILUX_TGN26 RM000000O8L0OLX.html).

    ECT
    Tester Display
    		Test Part
    		Control Range
    		Diagnostic Note
    Control the Shift Position
    		Operate shift solenoid valves and set each shift position
    1. Press "→" button: Shift up
    2. Press "←" button: Shift down
    		Possible to check operation of the shift solenoid valves.
    [Vehicle Condition]
    50 km/h (31 mph) or less
    HINT:
    1. This test can be conducted when the vehicle speed is 50 km/h (31 mph) or less.
    2. The 4th to 5th up-shift must be performed with the accelerator pedal released.
    3. The 5th to 4th down-shift must be performed with the accelerator pedal released.
    4. Do not operate the accelerator pedal for at least 2 seconds after shifting and do not shift successively.
    5. The shift position commanded by the TCM is shown in the Data List display on the tester.
    6. Shift solenoid valve S1 is turned ON/OFF normally when the shift lever is in D.

      TCM gear shift command
      		1st
      		2nd
      		3rd
      		4th
      		5th
      Shift solenoid valve S1
      		ON
      		ON
      		OFF
      		OFF
      		OFF
1.CHECK DTC OUTPUT (IN ADDITION TO DTC P0751)

  1. Connect the intelligent tester to the DLC3.

  1. Turn the ignition switch to ON.

  1. Turn the intelligent tester on.

  1. Enter the following menus: Powertrain / ECT / DTC.

  1. Read the DTCs using the tester.

    Result
    Result
    		Proceed to
    Only P0751 is output
    		A
    P0751 and other DTCs are output
    		B
    HINT:
    If any other codes besides P0751 are output, perform troubleshooting for those DTCs first.


B
GO TO DTC CHART (HILUX_TGN26 RM0000030G907BX.html)
A


2.PERFORM ACTIVE TEST USING INTELLIGENT TESTER (SHIFT SOLENOID VALVE SLT)
NOTICE:
  1. Perform the test while the ATF temperature is between 50 and 80°C (122 and 176°F).
  2. Be careful to prevent the hose of SST from interfering with the exhaust pipe.
  3. Perform the test with the A/C off.
HINT:
Using the intelligent tester to perform Active Tests 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 Tests early in troubleshooting is one way to save diagnostic time. Data List information can be displayed while performing Active Tests.


    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe). Dtc P0751 Shift Solenoid A Performance (Shift Solenoid Valve S1)

  1. Remove the test plug from the transmission case and connect SST.

SST
09992-00095(09992-00231,09992-00271)

  1. Connect the intelligent tester to the DLC3.

  1. Start the engine and warm it up.

  1. Measure the line pressure with SST.

  1. Turn the intelligent tester on.

  1. Enter the following menus: Powertrain / ECT / Active Test.

  1. According to the display on the tester, perform the Active Test.

  1. Measure the line pressure.

    ECT
    Tester Display
    		Test Part
    		Control Range
    		Diagnostic Note
    Activate the Solenoid (SLT)*
    		Operate shift solenoid valve SLT and raise line pressure
    		ON or OFF
    HINT:
    1. OFF: Line pressure up (when Active Test "Activate the Solenoid (SLT)" is performed, TCM commands shift solenoid valve SLT to turn OFF)
    2. ON: No action (normal operation)
    		[Vehicle Condition]
    1. Vehicle stopped
    2. Engine idling
    HINT:
    *: Activate the Solenoid (SLT) in the Active Test is performed to check the line pressure changes by connecting SST to the automatic transmission, which is used in the Hydraulic Test (HILUX_TGN26 RM000000W7B0P2X.html) as well. Note that the pressure values in the Active Test and hydraulic test are different.
    OK:
    The line pressure changes as specified when performing the Active Test.


NG
REPLACE SHIFT SOLENOID VALVE SLT (HILUX_TGN26 RM0000013FG02KX_01_0005.html)
OK


3.INSPECT SHIFT SOLENOID VALVE S1


    Hilux. Tgn26, 36 Kun25, 26, 35, 36 Ggn25.A750F Automatic Transmission Transaxle.Automatic Transmission System (For 1Gr-Fe). Dtc P0751 Shift Solenoid A Performance (Shift Solenoid Valve S1)

  1. Remove shift solenoid valve S1.

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

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

  1. 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
    1. Battery positive (+) → Shift solenoid valve S1 connector
    2. Battery negative (-) → Shift solenoid valve S1 body
    		Valve moves and makes an operating noise
Text in Illustration
*a
Component without harness connected
(Shift Solenoid Valve S1)


NG
REPLACE SHIFT SOLENOID VALVE S1 (HILUX_TGN26 RM0000013FG02KX_01_0007.html)
OK


4.INSPECT TRANSMISSION VALVE BODY ASSEMBLY

  1. Check the transmission valve body assembly (HILUX_TGN26 RM0000013FG02KX.html).

    OK:
    There are no foreign objects on any valve.


NG
REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY (HILUX_TGN26 RM0000013CM049X.html)
OK

REPAIR OR REPLACE AUTOMATIC TRANSMISSION ASSEMBLY (HILUX_TGN26 RM0000013F6019X.html)