P0715: Input/Turbine Speed Sensor A Circuit Malfunction
May cause transmission shift issues, limp/fail-safe mode, or erratic gear engagement
Overview
P0715 indicates a malfunction detected by the PCM/TCM in the input/turbine speed sensor circuit often due to wiring, sensor failure, or transmission issues
Common Symptoms
- Check Engine Light illuminated
- Harsh or erratic transmission shifting
- Limp mode activation
- Reduced fuel efficiency
- Incorrect speedometer/odometer readings
Most Common Causes
Sensor fails to provide valid RPM signal to PCM/TCM
Electrical circuit continuity issues can trigger the code
Physical damage can disrupt signal generation
Internal module issues can misinterpret or fail to receive signals
Fluid conditions can indirectly affect circuit readings
Diagnostic Steps
-
Connect OBD-II scanner and confirm P0715 code with freeze frame dataExpected: P0715 present without unrelated codesInterpretation: Confirms primary issue with input speed circuit
-
Visually inspect input/turbine speed sensor and wiring harness for damage, corrosion, or loose connectionsExpected: No damaged wires, connectors clean and intactInterpretation: Problems here likely cause of code
-
Measure sensor resistance and voltage with multimeter per OEM specsExpected: Resistance/voltage within manufacturer specificationsInterpretation: Out-of-spec readings indicate failed sensor
-
Inspect reluctor ring/shaft near sensor for physical damage or missing teethExpected: Reluctor ring intact with uniform teethInterpretation: Physical damage can disrupt accurate signal
-
If sensor and wiring appear functional, test PCM/TCM signal reception and consider scanning live input/output RPM dataExpected: Consistent RPM signal matches actual vehicle speedInterpretation: Mismatch suggests module or deeper transmission faults
Repair Solutions
Common and often necessary if sensor fails diagnostic tests
Costs vary depending on extent of harness damage
Requires internal access to transmission components
Only after ruling out sensor and wiring faults
Useful when fluid contamination contributes to issues
Common Misdiagnoses
Avoid these common diagnostic mistakes:
- Faulty output speed sensor instead of input sensor
- Internal transmission mechanical fault
- General engine misfire misinterpreted as sensor issue
User Comments (0)
Share your experience or ask a question about this code.
Please login to post a comment.
Be the first to share your experience with P0715!