How to Check the Code P0743 of Hyundai Sonata

How to Check the Code P0743 of Hyundai Sonata

Auto Repair and Study Guide

2009  G 2.4 DOHC  Transmission  Automatic Transaxle(A5GF1)  P0743 Torque Converter Clutch Circuit Electrical

Component Location Auto Repair and Study Guide w/ General Description The PCM/PCM/TCM controls the locking and unlocking of the Torque Converter Clutch ( or Damper Clutch ), to the input shaft of the transmission, by appling hydraulic pressure. The main purpose of T/C clutch control is to save fuel by decreasing the hydraulic load inside the T/C. The PCM/PCM/TCM outputs duty pulses to control the Damper Clutch Control Solenoid Valve( DCCSV ) and hydraulic pressure is applied to the DC according to the DCC duty ratio value. When the duty ratio is high, high pressure is applied and the Damper Clutch is locked. The normal operating range of the Damper Clutch Control duty ratio value is from 30%(unlocked) to 85%(locked). Auto Repair and DTC Description The PCM/PCM/TCM checks the Damper Clutch Control Signal by monitoring the feedback signal from the solenoid valve drive circuit. If an unexpected signal is monitored (for example, high voltage is detected when low voltage is expected, or low voltage is detected when high voltage is expected) the PCM/PCM/TCM judges that DCCSV circuit is malfunctioning and sets this code. DTC Detecting Condition Item Detecting Condition Possible Cause DTC Strategy • Check voltage range ※ TORQUE CONVERTER(DAMPER) CLUTCH : TCC • Open or short in circuit • Faulty TCC SOLENOID VALVE • Faulty PCM/TCM Enable Conditions • 16V  Voltage Battery 10V • In gear state(no gear shifting) 0.5sec is passed from turn on the relay Threshold Value • Feedback voltage from DCC control solenoide vb-2V and DCC control duty is 100% • Feedback voltage from DCC control solenoide 5.5V and DCC control duty is 0% Diagnostic Time • More than 0.3sec Fail Safe • Locked in 3 rd gear.(Control relay off) Specification Solenoid Valve for Pressure Control - Sensor type : Normal open 3-way - Operating temperature : -22~266°F(-30°C~130°C) - Frequency : LR, 2ND, UD, OD, RED : 61.27Hz (at the ATF temp. -20°C above) DCC : 30.64Hz ※ KM series : 35Hz - Internal resistance : 2.7~3.4Ω(68°F or 20°C) - Surge voltage : 56 V Schematic Circuit Diagram Auto Repair , Study Guide , Auto Repair Study Guide , Auto Repair , Study Guide more case and trouble Study