What does it mean?
OBD II fault code P0760 is a generic trouble code that is defined as, “Shift Solenoid “C”, and is set when the PCM (Powertrain Control Module) detects a failure, defect, malfunction, or an undefined problem in the shift solenoid labeled “C”, or in one or more control circuits that are associated with the shift solenoid labeled “C”. NOTE: Vehicle manufacturers do not follow a standard convention in how they label the shift solenoids in their transmissions.
Therefore, both the function of shift solenoid “C”, and the symptoms of defects in shift solenoid “C” may differ between vehicle makes and models, as well as between transmission types/designs. While the basic operating principles of automatic transmissions have not changed significantly over the past several decades, the complexity and sophistication of transmission control systems have changed greatly.
We need not delve into the complexities of these systems here, beyond saying that all modern automatic transmissions now use computer-controlled solenoids to direct and change the flow of pressurized transmission fluid. In practice, these solenoids are known as “shift solenoids” since they control the flow of fluid that acts on various components in the transmission.
For instance, if the PCM or TCM (Transmission Control Module) commands a gearshift, it accomplishes the shift by closing one solenoid, and opening another to direct pressurized fluid into another hydraulic circuit in the valve body. Thus, when one solenoid is closed, pressure is removed from the clutches that kept, say, first gear engaged, which disengages first gear.
By opening the next solenoid in the shift pattern, pressurized fluid enters another circuit through a series of valves, which engages second gear. In a fully functional transmission control system, the PCM/TCM obtains input data from several engine sensors, including (among several others) the- engine speed sensor vehicle speed sensor throttle position sensor throttle pedal position sensor steering angle sensor – to calculate appropriate shift points.
While these calculations are based primarily on the current engine speed and load, other factors include the current operating conditions, driving style, and the currently selected operating mode, i.e., Economy, Sport, or Performance. However, shift solenoid failures are fairly common across all manufacturers and transmission designs, so when such a failure occurs, the PCM/TCM will recognize that it cannot control the transmission effectively.
When this happens, the PCM/TCM will set an appropriate trouble code, and depending on the vehicle, may or may not illuminate a warning light. Note though that depending on both the nature of the failure and the vehicle, the PCM/TCM may initiate a fail-safe or limp mode as a precautionary measure that will typically persist until the fault is corrected.