Common Symptoms
- Speedometer erratic or inoperative
- Harsh or delayed transmission shifts
- Transmission stuck in one gear or limp mode
- Check Engine Light illuminated
- Poor fuel economy due to incorrect shift points
- ABS or traction control warning lights may also illuminate
Most Likely Root Causes
- Failed output speed sensor
- Damaged or corroded wiring harness to output speed sensor
- Poor electrical connection at sensor connector
- Internal transmission damage affecting reluctor wheel or tone ring
- Faulty transmission control module
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Component Location
The output speed sensor is typically mounted on the transmission case, monitoring the output shaft or tailshaft speed.
Manufacturer Notes
Some manufacturers use magnetic reluctance sensors while others use Hall effect sensors, requiring different diagnostic approaches.
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