Input/Turbine Speed Sensor Circuit Malfunction
What does P0715 mean?
The P0715 code means the vehicle's onboard diagnostic system has detected: Input/Turbine Speed Sensor Circuit Malfunction. This is a serious severity code.
Common Symptoms
- Harsh or erratic transmission shifting
- Transmission stuck in one gear
- Check Engine Light on
- Speedometer may be affected
Probable Causes (Ranked by Likelihood)
- Failed input shaft speed sensor Very High
- Damaged wiring or connector at input speed sensor Moderate
- Metal debris on sensor tip (from transmission wear) Moderate
Step-by-Step Diagnostic Procedure
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Monitor input shaft speed on a scan tool. At idle in drive with brakes applied, input speed should be near zero. Erratic readings indicate sensor or wiring issues.
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Test sensor resistance: 200-900 ohms for magnetic sensors.
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Remove the sensor and inspect the tip for metal shavings. Contamination can cause erratic readings.
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Inspect sensor wiring harness for damage at the transmission connector.
Frequently Asked Questions
What does the input speed sensor do?
The input (turbine) speed sensor measures the rotational speed of the torque converter turbine, which is the input shaft of the transmission. The TCM uses this to determine slip, torque converter lockup timing, and shift points.