P0715 indicates a malfunction in the electrical circuit for the input or turbine shaft speed sensor. This sensor measures the rotational speed of the transmission input shaft, which the vehicle's computer uses to determine shift timing and torque converter operation. A fault in this circuit prevents the computer from accurately reading the input speed, often forcing the transmission into a protective limp mode.
The sensor itself can fail internally due to heat and vibration, causing an open or shorted circuit that prevents signal generation.
Corroded, frayed, or disconnected wiring and connectors in the sensor circuit are highly common and interrupt the signal to the control module.
Insufficient or contaminated fluid can interfere with the sensor's magnetic reading, while metal shavings in the fluid can accumulate on the sensor tip.
The internal toothed wheel that the sensor reads can become chipped, cracked, or misaligned due to internal transmission wear, disrupting the signal.
A failure within the powertrain or transmission control module is extremely rare and should only be considered after all other possibilities are eliminated.
It is not recommended. The transmission will likely enter limp mode, restricting speed and gear selection, and driving in this state can cause further internal transmission damage.
No. The input/turbine speed sensor measures the speed of the fluid entering the transmission from the engine, while the output speed sensor measures the speed leaving the transmission toward the driveshaft.
Almost never. It is a common misconception that the computer is bad when this code appears, but the root cause is almost always a failed sensor, damaged wiring, or a fluid issue. Replacing the control module will not fix the underlying physical problem.
Ignoring the code will result in continued harsh or erratic shifting, poor fuel economy, and the risk of the vehicle entering limp mode unexpectedly, which could leave you stranded.