P0756
A750E AUTOMATIC TRANSMISSION: AUTOMATIC TRANSMISSION SYSTEM (for 1GR-FE): P0756: Shift Solenoid "B" Performance (Shift Solenoid Valve S2)
DTC P0756 - Shift Solenoid "B" Performance (Shift Solenoid Valve S2)
DESCRIPTION
The ECM 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 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 transmission (clutch, brake or gear, etc.).
MONITOR DESCRIPTION
This DTC indicates "stuck ON malfunction" or "stuck OFF malfunction" of the shift solenoid valve S2.
The ECM commands gear shifts by turning the shift solenoid valves "ON/OFF". 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.
MONITOR STRATEGY
TYPICAL ENABLING CONDITIONS
All
OFF malfunction (A)
OFF malfunction (B)
OFF malfunction (C)
OFF malfunction (D)
ON malfunction (A)
ON malfunction (B)
ON malfunction (C)
ON malfunction (D)
TYPICAL MALFUNCTION THRESHOLDS
[OFF malfunction]
- All of the following conditions are met: OFF malfunction (A), (B), (C) and (D)
2 detections are necessary per driving cycle
1st detection: temporary flag ON
2nd detection: pending fault code ON
OFF malfunction (A)
OFF malfunction (B)
OFF malfunction (C)
OFF malfunction (D)
[ON malfunction]
- Both of the following conditions are met: ON malfunction (A) or (B), and ON malfunction (C) or (D)
ON malfunction (A)
ON malfunction (B)
ON malfunction (C)
ON malfunction (D)
INSPECTION PROCEDURE
1. ACTIVE TEST
HINT: Using Techstream 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.
(a) Warm up the engine.
(b) Turn the ignition switch OFF.
(c) Connect Techstream to the DLC3.
(d) Turn the ignition switch ON, and turn the tester main switch ON.
(e) Enter the following menus: Powertrain / Engine and ECT / Active Test.
(f) Follow the instructions on the tester and 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 Fail-Safe Chart.
Engine and ECT
HINT:
- This test can be conducted when the vehicle speed is 50 km/h (31 mph) or less.
- The 4th to 5th up-shift must be performed with the accelerator pedal released.
- The 5th to 4th down-shift must be performed with the accelerator pedal released.
- Do not operate the accelerator pedal for at least 2 seconds after shifting and do not shift successively.
- The shift position commanded by the ECM is shown in the Data List display on Techstream.
- The shift solenoid valve S1 turns ON/OFF normally when the shift lever is in the D position:
PROCEDURE
1. CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P0756)
(a) Connect Techstream to the DLC3.
(b) Turn the ignition switch ON, and turn the tester main switch ON.
(c) Enter the following menus: Powertrain / Engine and ECT / Trouble Codes.
(d) Read the DTCs using Techstream.
Result:
HINT: If any other codes besides P0756 are output, perform troubleshooting for those DTCs first.
B -- GO TO DTC CHART
A -- Continue to next step.
2. PERFORM ACTIVE TEST USING TECHSTREAM (SHIFT SOLENOID VALVE SLT)
NOTICE:
- Perform the test at the normal operating ATF temperature: 50 to 80°C (122 to 176°F).
- Be careful to prevent SST's hose from interfering with the exhaust pipe.
- Perform the test with the A/C OFF.
HINT:
Performing Techstream's Active Test allows relays, VSVs, actuators and other items to be operated without removing any parts. Performing the Active Test early in troubleshooting is one way to save time. The Data List can be displayed during the Active Test.
(a) Remove the test plug on the transmission case center right side and connect SST.
SST: 09992-00095
09992-00231
09992-00271
(b) Connect Techstream to the DLC3.
(c) Start the engine and warm it up.
(d) Measure the line pressure with SST.
(e) Turn Techstream ON.
(f) Enter the following menus: Powertrain / Engine and ECT / Active Test.
(g) Follow the instructions on the tester and perform the Active Test.
(h) Measure the line pressure with SST.
Engine and ECT
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 Hydraulic Test as well. Please 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
OK -- Continue to next step.
3. INSPECT SHIFT SOLENOID VALVE S2
(a) Remove the shift solenoid valve S2.
(b) Measure the resistance of the solenoid valve.
Standard resistance:
(c) Connect the battery's positive (+) lead to the terminal of the solenoid valve connector, and the negative (-) lead to the solenoid body. Then check that the valve moves and makes an operating noise.
OK:
Valve moves and makes an operating noise.
NG -- REPLACE SHIFT SOLENOID VALVE S2
OK -- Continue to next step.
4. INSPECT TRANSMISSION VALVE BODY ASSEMBLY
(a) Check the transmission valve body assembly Disassembly.
OK:
There are no foreign objects on any valve.
NG -- REPAIR OR REPLACE TRANSMISSION VALVE BODY ASSEMBLY
OK -- REPAIR OR REPLACE AUTOMATIC TRANSMISSION ASSEMBLY