CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P2757)
INSPECT SHIFT SOLENOID VALVE SLU
INSPECT TRANSMISSION VALVE BODY ASSEMBLY
INSPECT TORQUE CONVERTER CLUTCH ASSEMBLY
DTC P2757 Torque Converter Clutch Pressure Control Solenoid Performance (Shift Solenoid Valve SLU) |
SYSTEM DESCRIPTION
The TCM uses the signals from the throttle position sensor, air-flow meter, turbine (input) speed sensor, output speed sensor and crankshaft position sensor to monitor the engagement condition of the lock-up clutch.
The TCM compares the engagement condition of the lock-up clutch with the lock-up schedule in the TCM memory to detect shift solenoid valve SLU, valve body and torque converter clutch mechanical problems.
DTC No. | DTC Detection Condition | Trouble Area |
P2757 | When both of the following are detected (2-trip detection logic):
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MONITOR DESCRIPTION
Torque converter lock-up is controlled by the TCM based on the turbine (input) speed sensor NT, output speed sensor NC, engine rpm, engine load, engine temperature, vehicle speed, transmission fluid temperature, and gear selection. The TCM determines the lock-up status of the torque converter by comparing the engine rpm (NE) to the input turbine rpm (NT). The TCM calculates the actual transmission gear by comparing input turbine rpm (NT) to output shaft rpm (NC). When conditions are appropriate, the TCM requests "lock-up" by applying control voltage to the shift solenoid SLU. When the SLU is turned on, it applies pressure to the lock-up relay valve and locks the torque converter clutch.If the TCM detects no lock-up after lock-up has been requested or if it detects lock-up when it is not requested, the TCM interprets this as a fault in the shift solenoid valve SLU or lock-up system performance.
The TCM will turn on the MIL and store the DTC.
Example:
When any of the following is met, the system judges it as a malfunction.
- There is a difference in rotation between the input side (engine speed) and output side (input turbine speed) of the torque converter when the TCM commands lock-up.
(Engine speed is at least 70 rpm greater than input turbine speed.) - There is no difference in rotation between the input side (engine speed) and output side (input turbine speed) of the torque converter when the TCM commands lock-up off.
(The difference between engine speed and input turbine speed is less than 20 rpm.)
INSPECTION PROCEDURE
ACTIVE TEST |
- HINT:
- Performing the Active Test using the intelligent tester allows relays, VSVs, actuators and other items to be operated without removing any parts. Performing the Active Test as the first step in troubleshooting is one method to save labor time.
- It is possible to display the Data List during the Active Test.
Warm up the engine.
Turn the ignition switch off.
Connect the intelligent tester to the DLC3.
Turn the ignition switch on.
Turn on the tester.
Enter the following items: "Powertrain / ECT / Active Test".
According to the display on the tester, perform "Active Test".
Item Test Details Diagnostic Note Activate the Lock Up [Test Details]
Control the shift solenoid SLU to set the automatic transaxle to the lock-up condition.
[Vehicle Condition]- Throttle valve opening angle: Less than 35%
- Vehicle Speed: 60 km/h (37 mph) or more
Possible to check the SLU operation. - HINT:
- This test can be conducted when the vehicle speed is 60 km/h (37 mph) or more.
- This test can be conducted with the 6th gear.
- Throttle valve opening angle: Less than 35%
Lightly depress the accelerator pedal and check that the engine speed does not change abruptly.
- HINT:
- When changing the accelerator pedal opening angle while driving, if the engine speed does not change, lock-up is on.
- Slowly release, but not fully, the accelerator pedal in order to decelerate. (Fully releasing the pedal will close the throttle valve and lock-up may be turned off automatically.)
1.CHECK OTHER DTCS OUTPUT (IN ADDITION TO DTC P2757) |
Connect the intelligent tester to the DLC3.
Turn the ignition switch on and turn the intelligent tester on.
Enter the following items: "Powertrain / ECT / DTC / Current or Pending".
Read the DTCs using the intelligent tester.
- Result:
Display (DTC output) Proceed to Only "P2757" is output A "P2757" and other DTCs B
- HINT:
- If any other codes besides "P2757" are output, perform troubleshooting for those DTCs first.
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A | |
2.INSPECT SHIFT SOLENOID VALVE SLU |
Remove the shift solenoid valve SLU.
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Measure the resistance according to the value(s) in the table below.
- Standard resistance:
Tester Connection Specified Condition
20°C (68°F)1 - 2 5.0 to 5.6 Ω
Connect a positive (+) lead through a 21 W bulb to terminal 2 and a negative (-) lead to terminal 1 of the solenoid valve connector, then check the movement of the valve.
- OK:
- The solenoid makes an operating sound.
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OK | |
3.INSPECT TRANSMISSION VALVE BODY ASSEMBLY |
- OK:
- There are no foreign objects on each valve.
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OK | |
4.INSPECT TORQUE CONVERTER CLUTCH ASSEMBLY |
Check the torque converter clutch assembly (CAMRY_ACV40 RM000000YXK00JX.html).
- OK:
- The torque converter clutch operates normally.
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OK | ||
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