What does this code mean?
A sensor measures rotational speed at the gearbox input; it does not directly measure road speed. P0715 indicates a problem with that measurement circuit. The sensor, connections and wiring need checking before concluding that the gearbox has failed.
Locate the reported problem
Input/turbine speed is not the same as wheel speed or transmission output speed. Sensor location and naming can differ between conventional automatics and CVTs.
Read it with the other codes
P0700 may accompany a detailed transmission fault, while P0741 concerns converter lockup performance. Verify the speed signal before relying on comparisons that use it.
Possible causes to investigate
These are possibilities, not a diagnosis or a ranked list of failed parts.
- A speed signal, electrical supply or control-circuit issue requiring targeted checks.
- A hydraulic or mechanical condition whose diagnosis depends on the detailed transmission codes and data.
What to do first
- Save the full report, including the module that supplied each code. Note shift behavior, slipping, temperature warnings and recent service.
- Do not add fluid or additives based only on a code. If the vehicle loses drive, shifts violently or overheats, stop safely and arrange assistance.
What the workshop can check
Use a tool with coverage for the exact transmission controller (TCM), retrieve its detailed faults and compare relevant data. Generic OBD access may show an engine-side warning without the transmission detail; absence of additional codes in that scan does not prove the transmission is fault-free.
A useful question to ask
Is the input-speed signal missing or unreliable, and were its supply, wiring and signal target checked?
Your vehicle changes the next step
Year, make, model, engine and the complete code list matter. Cylinder layout, test conditions and repair procedures can differ. Use service information for the exact vehicle; a generic code does not establish an exact failed part.
Can I keep driving?
This page cannot decide whether your car is safe to drive. A flashing engine light, severe shaking, overheating, strong fuel smell or major power loss calls for prompt attention. Stop safely when needed, follow your handbook and seek assistance rather than continuing a test drive.
Terms in this guide
These words appear in the explanation. Select an underlined term in the text to reach its definition.
- Sensor and signal
- A sensor measures something such as pressure or temperature. Its signal carries that information electrically to the car computer; a wrong reading does not always mean the measured component is faulty.
- Transmission and TCM
- The transmission or gearbox adapts engine rotation to drive the wheels. TCM is its control computer. Reading it may require equipment with vehicle-specific coverage.
- Circuit, supply and ground
- A circuit includes the wiring and connections carrying electricity. Supply powers a component; ground is its electrical return. A fault in any of these can change a reading.
- CVT and input speed
- A CVT is a gearbox with a continuously changing ratio. Input speed describes rotation on the side receiving engine power, not wheel speed.
- Control unit
- A car computer that receives measurements and controls the engine or another system. It may also be called a module, ECU, ECM or PCM.
- Torque converter and lockup
- In many automatic gearboxes it transfers power through fluid. Its lockup clutch makes a more direct connection under certain conditions to reduce losses.
- Range, threshold and performance
- A range is the expected interval; a threshold is a comparison limit. Performance describes whether something responds as expected, not necessarily how much power the engine makes.
- Hydraulic
- Operating through pressurized fluid, as in parts of automatic gearbox control.
Sources and scope
Definitions and general OBD context are cross-checked against the references below. Manufacturer documents describe specific vehicles and systems; their procedures and thresholds are not instructions for every make. This is educational guidance, not a vehicle-specific repair procedure.