P0740

P0740 TORQUE CONVERTER CLUTCH SOLENOID VALVE

Description
^ The torque converter clutch solenoid valve is activated, with the gear in D3, D4, D5, M3, M4 and M5 by the TCM in response to signals transmitted from the vehicle speed sensor and accelerator pedal position sensor (throttle position sensor). Torque converter clutch piston operation will then be controlled.
^ Lock-up operation, however, is prohibited when A/T fluid temperature is too low.
^ When the accelerator pedal is depressed (less than 1.0/8) in lock-up condition, the engine speed should not change abruptly. If there is a big jump in engine speed, there is no lock-up.

DTC Logic

P0740:

DTC CONFIRMATION PROCEDURE

CAUTION: Always drive vehicle at a safe speed.

NOTE: If "DTC CONFIRMATION PROCEDURE" has been previously performed, always turn ignition switch OFF. Then wait at least 10 seconds before performing the next test.

1. CHECK DTC DETECTION

With CONSULT-III
1. Start the engine.
2. Select "Data Monitor" mode for "TRANSMISSION".
3. Drive vehicle and maintain the following conditions for at least 5 consecutive seconds.
VHCL/S SE-A/T: 80 km/h (50 MPH) or more
ACCELE POSI: 0.5/8 - 1.0/8
SLCT LVR POSI: "D" position
Drive location: Driving the vehicle uphill (increased engine load) will help maintain the driving conditions required for this test.

With GST
Follow the procedure "With CONSULT-III".
Is "P0740 TCC SOLENOID/CIRC" detected?
YES >> Go to "Diagnosis Procedure".
NO >> Check intermittent incident. Refer to GI-38, "Intermittent Incident". Service Information For Electrical Incident

Diagnosis Procedure

1. CHECK TCM POWER SUPPLY AND GROUND CIRCUIT
Check TCM power supply and ground circuit. Refer to TM-89, "Diagnosis Procedure". Main Power Supply and Ground Circuit
Is the inspection result normal?
YES >> Replace the control valve with TCM.
NO >> Repair or replace damaged parts.