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.

Fig 1: Identifying Shift Solenoid Valve SLU Components And Hydraulic Line Pressure Graph

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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): Lock-up does not occur when requested. Transmission fluid pressure switch No. 3 is OFF. When both of the following are detected (2-trip detection logic): Transmission fluid pressure switch No. 3 is ON when lock-up does not occur. Lock-up occurs when shift solenoid valve SLU is requested to turn on in the lock-up range.	Shift solenoid valve SLU remains open or closed Valve body is blocked Torque converter clutch Automatic transaxle (clutch, brake or gear, etc.) Line pressure is too low

DTC No.

DTC Detection Condition

Trouble Area

P2757

When both of the following are detected (2-trip detection logic):

Lock-up does not occur when requested.
Transmission fluid pressure switch No. 3 is OFF.

When both of the following are detected (2-trip detection logic):

Transmission fluid pressure switch No. 3 is ON when lock-up does not occur.
Lock-up occurs when shift solenoid valve SLU is requested to turn on in the lock-up range.

Shift solenoid valve SLU remains open or closed
Valve body is blocked
Torque converter clutch
Automatic transaxle (clutch, brake or gear, etc.)
Line pressure is too low