P0715
Input/Turbine Speed Sensor Circuit Malfunction
high
i Description
The transmission input speed sensor (also called the turbine speed sensor) circuit has a malfunction. This sensor measures the rotational speed of the torque converter turbine/transmission input shaft, which the TCM uses to calculate shift timing and torque converter slip.
? Common Causes
- Faulty input speed sensor
- Damaged wiring or connector
- Contaminated transmission fluid causing sensor issues
- Internal transmission fault affecting sensor signal
! Symptoms
- Check engine light
- Harsh or erratic shifting
- Transmission may not shift correctly
- Speedometer issues (some vehicles)
- Limp mode
# Diagnostic Steps
- Check transmission fluid level and condition
- Test input speed sensor resistance
- Inspect wiring and connector for damage
- Compare input and output speed sensor signals
- Replace sensor if signal is absent
⚙ Typical Fix
Replace the input speed sensor. This often requires dropping the transmission pan or valve body.
Parts Needed
Input speed sensor, Transmission filter, Transmission fluid, Pan gasket
Estimated Cost
$150-$500
↔ Related Codes
Q Frequently Asked Questions
The transmission may shift erratically or be stuck in one gear. Drive carefully at low speeds to a mechanic. Avoid highway driving.
Input speed sensor: $20-$80. Labour: $100-$300 (requires dropping the trans pan on most vehicles). It is a good idea to change the fluid and filter at the same time.
☞ Learn More
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