Dtc P0746 Pressure Control Solenoid A Performance (Shift Solenoid Valve Sl1)

Drivetrain. Corolla. Zre142 Aze141
U250E Automatic Transmission Transaxle. Corolla. Zre142 Aze141

SYSTEM DESCRIPTION

MONITOR DESCRIPTION

MONITOR STRATEGY

TYPICAL ENABLING CONDITIONS

TYPICAL MALFUNCTION THRESHOLDS

INSPECTION PROCEDURE

CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P0746)

INSPECT SHIFT SOLENOID VALVE SL1

INSPECT TRANSMISSION VALVE BODY ASSEMBLY

INSPECT TORQUE CONVERTER ASSEMBLY

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


SYSTEM DESCRIPTION

The ECM uses signals from the vehicle speed sensor to detect the actual gear position (1st, 2nd, 3rd, 4th or 5th 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.).

Corolla. Zre142 Aze141.U250E Automatic Transmission Transaxle.Automatic Transaxle System. Dtc P0746 Pressure Control Solenoid A Performance (Shift Solenoid Valve Sl1)


DTC No.
DTC Detecting Condition
Trouble Area
P0746
The gear required by the ECM does not match the actual gear when driving (2-trip detection logic)
  1. Shift solenoid valve SL1 remains open or closed
  2. Valve body is blocked
  3. 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, 4th or 5th 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.
HINT:
Example:
When either condition (a) or (b) is met, the ECM detects a malfunction.
(a) The ECM commands the 1st gear, but the actual gear is 2nd.
(b) The ECM commands the 2nd gear, but the actual gear is 1st.

MONITOR STRATEGY


Related DTCs
P0746:
Shift solenoid valve SL1/OFF malfunction
Shift solenoid valve SL1/ON malfunction
Required sensors/Components
Shift solenoid valve SL1, Speed sensor (NT), Speed sensor (NC), Crankshaft position sensor (NE)
Frequency of operation
Continuous
Duration
0.8 sec.
MIL operation
2 driving cycles
Sequence of operation
None

TYPICAL ENABLING CONDITIONS


ALL:
The monitor will run whenever this DTC is not present.
(Not circuit malfunction)
P0712, P0713 (ATF temperature sensor circuit)
P0115, P0117, P0118 (ECT sensor circuit)
P0717 (Turbine speed sensor circuit)
P0793 (Intermediate shaft speed sensor circuit)
P0500 (Vehicle speed sensor circuit)
P0748 (Shift solenoid valve SL1 circuit)
P0778 (Shift solenoid valve SL2 circuit)
P0798 (Shift solenoid valve SL3 circuit)
P0982, P0983 (Shift solenoid valve S4 circuit)
P0985, P0986 (Shift solenoid valve SR circuit)
P2769, P2770 (Shift solenoid valve DSL circuit)
P0120, P0121, P0122, P0123, P0220, P0222, P0223, P0604, P0606, P0607, P060A, P060D, P060E, P0657, P1607, P2102, P2103, P2111, P2112, P2118, P2119, P2135 (Electronic throttle system)
ECT (Engine coolant temperature)
10°C (50°F) or more
Transmission range
"D"
TFT (Transmission fluid temperature)
-20°C (-4°F) or more

OFF malfunction:
ECM selected gear
1st
Vehicle speed
Less than 40 km/h (25 mph)
Throttle valve opening angle
4.5% or more at engine speed 1900 rpm
(Varies with engine speed)

ON malfunction:
ECM selected gear
2nd
Throttle valve opening angle
4.5% or more at engine speed 1900 rpm
(Varies with engine speed)

TYPICAL MALFUNCTION THRESHOLDS

Either of the following conditions is met: OFF malfunction or ON malfunction
  1. 2 detections are necessary per driving cycle:
    1st detection; temporary flag ON
    2nd detection; pending fault code ON

    OFF malfunction:
    Input (turbine) speed/Intermediate shaft speed
    		1.49 to 1.63

    ON malfunction:
    Input (turbine) speed/Intermediate shaft speed
    		2.72 to 2.86

INSPECTION PROCEDURE

NOTICE:
Perform the universal trip to clear permanent DTCs (COROLLA_ZRE142 RM000000W770S6X.html).
HINT:
Using Techstream 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.

PERFORM ACTIVE TEST

  1. Warm up the engine.

  2. Turn the ignition switch off.

  3. Connect Techstream to the DLC3.

  4. Turn the ignition switch to the on position.

  5. Turn on the tester.

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

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

    HINT:
    While driving, the shift position can be forcibly changed with Techstream.
    Comparing the shift position commanded by the Active Test with the actual shift position enables you to confirm the problem (COROLLA_ZRE142 RM000000O8L0N2X.html).

    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]
    1. IDL: ON
    2. Less than 50 km/h (31 mph)
    [Others]
    1. Press "→" button: Shift up
    2. Press "←" button: Shift down
    		1st/2nd/3rd/4th/5th
    		Possible to check the operation of the shift solenoid valves.
    HINT:
    1. This test can be conducted when the vehicle speed is 50 km/h (31 mph) or less.
    2. The shift position commanded by the ECM is shown in the Data List / Shift Status display on Techstream.
1.CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P0746)

  1. Connect Techstream to the DLC3.

  1. Turn the ignition switch to the on position and turn the Techstream main switch ON.

  1. When you use Techstream:
    Select the item "Powertrain / Engine and ECT / Trouble Codes".

  1. Read the DTCs using Techstream.

    Result:

    Display (DTC output)
    		Proceed to
    Only "P0746" is output
    		A
    "P0746" and other DTCs
    		B
    HINT:
    If any other codes besides "P0746" are output, perform the troubleshooting for those DTCs first.


B
GO TO DTC CHART (COROLLA_ZRE142 RM000000W710LJX.html)
A


2.INSPECT SHIFT SOLENOID VALVE SL1


    Corolla. Zre142 Aze141.U250E Automatic Transmission Transaxle.Automatic Transaxle System. Dtc P0746 Pressure Control Solenoid A Performance (Shift Solenoid Valve Sl1)

  1. Remove the shift solenoid valve SL1.

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

    Standard resistance:
    Tester Connection
    		Condition
    		Specified Condition
    1 - 2
    		20°C (68°F)
    		5.0 to 5.6 Ω

  1. Connect the positive (+) lead with a 21 W bulb to terminal 2 and the negative (-) lead to terminal 1 of the solenoid valve connector, then check the movement of the valve.

    OK:
    The solenoid makes an operating sound.


NG
REPLACE SHIFT SOLENOID VALVE SL1 (COROLLA_ZRE142 RM00000109S01BX.html)
OK


3.INSPECT TRANSMISSION VALVE BODY ASSEMBLY
OK:
There are no foreign objects on each valve and they operate smoothly.


NG
REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY (COROLLA_ZRE142 RM000000YWX02NX.html)
OK


4.INSPECT TORQUE CONVERTER ASSEMBLY
OK:
The torque converter assembly operates normally.


NG
REPLACE TORQUE CONVERTER ASSEMBLY
OK

REPAIR OR REPLACE AUTOMATIC TRANSAXLE ASSEMBLY (COROLLA_ZRE142 RM000000YWV032X.html)