Common Symptoms
- Speedometer reads zero or intermittently drops to zero while driving
- ABS warning light illuminated
- Transmission shifts erratically or stays in one gear
- Cruise control inoperative or disengages unexpectedly
- Check Engine Light illuminated
- Traction control or stability control warning lights on
Most Likely Root Causes
- Faulty vehicle speed sensor
- Damaged or corroded wiring harness to speed sensor
- Poor electrical connection at speed sensor connector
- Failed tone ring or reluctor ring on transmission or differential
- Faulty instrument cluster or powertrain control module
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Component Location
Vehicle speed sensor is typically mounted on the transmission tail housing or differential case, depending on vehicle design.
Manufacturer Notes
Some vehicles use transmission output shaft speed sensors while others use wheel speed sensors for vehicle speed calculation.
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