Lexus Transmission Problemsby Pat Martin
Lexus first released the four-speed automatic electronic control transmission with intelligence (ECT-i) in 1992. The Lexus transmission includes the transaxle and all its parts, the torque converter, clutch cover, transmission mounts, engine control computer, seals and gaskets. Power is transferred to the transaxle from the transfer case above the transmission.
Torque Converter Fault Codes
The electronic throttle motor integrates information from the transfer case and torque changes associated with accelerating and decelerating and smooths the air-fuel ratio. Therefore, transmission problems produce fault codes in the car's memory. Transmission fault codes are P0700 to P0999. A torque converter malfunction creates a P0719 or P0724 fault code.
Automatic Transmission Fluid Fault Codes
Your Lexis transmission is a sealed unit, which contains automatic transmission fluid. If the transmission fluid is dirty or of an improper temperature, your Lexus will not shift correctly and will produce fault codes of P0840 to P0849 or P0867 to P0869. If a solenoid switch malfunctions, the transmissions produces fault codes of P0750 to P0779.
Transmission and Solenoid Fault Codes
Solenoids open or close due to electrical current supplied by the transmission. If your transmission control unit malfunctions, the transmission produces P0859 to P0866 fault codes. If part of the transmission malfunctions, the fault code between P0900 and P0999 tells exactly which component failed.