P0715Powertrain
Powertrain · SAE
Input/Turbine Speed Sensor A Circuit
Meaning
An electrical fault has been detected in the circuit of the transmission input shaft speed sensor or torque converter turbine speed sensor. The TCM is not receiving a valid signal from this sensor. The code indicates an electrical issue such as an open circuit, short circuit, or out-of-range voltage.
Common causes
- Failed input/turbine speed sensor
- Open circuit or short circuit in the sensor wiring harness
- Damaged, oxidized, or disconnected sensor connector
- Damaged reluctor ring with missing or broken teeth
- Internal TCM fault
Symptoms
- Malfunction indicator lamp (MIL) illuminated
- Transmission in limp/fail-safe mode
- Absent, harsh, or unpredictable gear shifts
- Abnormal traction control or ABS intervention
- Inability to engage certain gears
Severity
High severity: without a valid input speed signal the TCM cannot correctly manage gear changes, risking mechanical damage to the transmission.
What to do
- Read fault codes and check transmission input speed live data
- Inspect the sensor connector and wiring for shorts, open circuits, and corrosion
- Measure sensor resistance and supply voltage against manufacturer specifications
- Visually inspect the reluctor ring for damage, deformation, or missing teeth
- Replace the sensor if defective; evaluate the TCM if wiring and sensor are intact