Review the 'Possible Causes' mentioned above and visually examine the corresponding wiring harness and connectors. Ensure to check for any damaged components and inspect the connector pins for signs of being broken, bent, pushed out, or corroded.
When a transmission solenoid malfunction, in most cases the problem is not the electrical part of the solenoid; the problem is foreign material obstructing the mechanical function of the solenoid or the flow of the fluid through the transmission valve body. If the transmission fluid is dirty, it's recommended to change the transmission fluid and if possible, remove the transmission pan for further diagnosis. Excessive debris or metal particles on the transmission pan could be an indication that there is a mechanical transmission failure, and that the transmission will need to be rebuilt or replaced.
Search for P0748 Lexus Questions and Answers: Search here →
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P0748 Lexus code, it typically requires 1.0 hour of labor. The specific diagnosis time and labor rates at auto repair shops can differ based on factors such as the location, make and model of the vehicle, and even the engine type. It is common for most auto repair shops to charge between $75 and $150 per hour.
What are Code Possible Symptoms?
Engine Light ON (or Service Engine Soon Warning Light)
Transmission shift shock
Code P0748 Lexus Description
Changing from 1st to 6th is performed by the Engine Control Module (ECM) turning shift solenoid valves SL1, SL2, SL3, SL4, and SL on and off. If an open or short circuit occurs in any of the shift solenoid valves, the ECM controls the remaining normal shift solenoid valves to allow the vehicle to be operated.
This Diagnostic Trouble Code (DTC) indicates an open or short in the shift solenoid valve SL1 circuit. The ECM commands gear shifts by turning the shift solenoid valves on or off. When there is an open or short circuit in any shift solenoid valve circuit, the ECM detects the problem and illuminates the MIL, and stores the DTC. The ECM also performs the fail-safe function and turns the other normal shift solenoid valves on or off. (In case of an open or short circuit, the ECM stops sending current to the circuit.)
While driving and shifting between the 4th and 5th gears, if the ECM detects an open or short in the shift solenoid valve SL1 circuit, the ECM determines there is a malfunction.
P0748 Lexus Code - Pressure Control Solenoid 'A' Electrical
Help us improve AutoCodes.com. Leave a comment below or tell us if the information above helps you fix the code. What are the symptoms on your vehicle for the P0748 Lexus code? Have you replaced any parts? Any information is appreciated. Thanks