Common Symptoms
- Check Engine Light illuminated
- Speedometer erratic or inoperative
- Transmission shifting problems or harsh shifts
- Loss of cruise control function
- Transmission may stay in limp mode or fail-safe
- Poor fuel economy due to incorrect shift points
Most Likely Root Causes
- Faulty output speed sensor
- Damaged or corroded wiring harness to output speed sensor
- Internal transmission mechanical issues affecting sensor tone ring
- Transmission control module software issue
- Loose or corroded electrical connector at sensor
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Component Location
The output speed sensor is typically mounted on the transmission case near the output shaft or tailhousing.
Manufacturer Notes
Some manufacturers require transmission fluid level and condition verification as sensor readings can be affected by low fluid or internal slippage.
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