Common Symptoms
- Check Engine Light illuminated
- Transmission shifts erratically or harshly
- Speedometer operates intermittently or not at all
- Transmission stuck in one gear or limp mode
- Poor fuel economy
- Vehicle fails to shift properly under acceleration
Most Likely Root Causes
- Faulty input speed sensor
- Damaged wiring harness or connector to input speed sensor
- Low transmission fluid level causing sensor malfunction
- Internal transmission mechanical damage affecting sensor tone ring
- Corroded or contaminated sensor connector terminals
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Component Location
The input speed sensor is typically mounted on the transmission case near the torque converter or input shaft area.
Manufacturer Notes
Some manufacturers require transmission fluid replacement and adaptive learning reset after input speed sensor replacement.
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