What is a Vehicle Speed Sensor?
In order for systems like anti lock brakes, traction control, and the speedometer to function properly, the ABS control module and Powertrain control module must know the speed the wheels should be spinning, as well as the speed the wheels are actually spinning. To create the data the computer needs for the speed the vehicle should be spinning, the transmission output shaft speed, for most vehicles, is measured by the vehicle speed sensor. The vehicle speed sensor will detect the speed of the output shaft many times per second, and send that data to the necessary control units for further use.
How does a Vehicle Speed Sensor work?
As the output shaft for the transmission turns, a ring on the output shaft spins very closely to the vehicle speed sensor, allowing the sensor to read how fast the ring is spinning by features on the ring. The speed of the output shaft, then, is reported back to various control modules by a digital or analog signal, whichever the control unit is designed to interpret. This is used to show the vehicle speed on the speedometer, but also has applications for the anti-lock brake system and traction control system since the information can be compared to wheel and engine speed.
What are the symptoms of a bad Vehicle Speed Sensor?
When the vehicle speed sensor fails or the wiring harness prevents signal transmission, the speedometer is the first thing that will stop functioning properly. This can be an intermittent issue where the speedometer only works occasionally, the speedometer may cease all function, or the speedometer may read erratically or incorrectly. Also, the traction control and anti lock brake warning lights specific to each vehicle may be illuminated, depending on the design of those systems. You may notice the vehicle hesitate to accelerate, cruise control will not function properly, and the vehicle may not shift properly through all of the gears.
Can I drive with a bad Vehicle Speed Sensor?
Testing and replacement of the speed sensor should be done as soon as possible, but in the case that the speedometer is the only thing affected, normally older vehicles, the vehicle can be driven until the sensor is tested and replaced. It should be mentioned that driving without a speedometer is illegal in most locations, and if the anti lock brakes and traction control are disabled, the vehicle will be more prone to sliding under heavy braking or acceleration.
How often do Vehicle Speed Sensors need replacement?
The vehicles that will experience the highest rate of failure for the vehicle speed sensor are those that are left unmaintained. As transmission fluid ages and becomes contaminated, those contaminates will become stuck to the speed sensor or ring, and prevent accurate readings. If the powertrain control module cannot read the vehicle speed, even though the sensor is working properly, the result will be the same as if the sensor had failed. Generally, a vehicle speed sensor should last well over 100,000 miles, and the average replacement frequency is closer to 150,000 miles, with exceptions. To prolong the life of your vehicle speed sensor, as well as all other components in your transmission, ensure you are maintaining the transmission in accordance with the owners manual service and maintenance section.
- Questions
- /
- Ford
- /
- Taurus
- /
- 2008
- /
- Where is the output speed...
2008 Ford Taurus
Asked by marcanddulsie in Columbus, IN on July 21, 2013
needing to know where to find the output speed sensor on a 2008 ford taurus limited.
1 reply Report
Answer
Popular Answer
mrfordman on July 30, 2013
output shaft speed sensor is located inside the transmission. have to pull front pan and valve body. takes about 4 hours.
Sign in to reply
Get back on the road
- Find auto repair near me
- Troubleshoot a car problem
- Ask a 2008 Ford Taurus question
- Free Ford Taurus repair estimates
- Car care advice
Get back on the road
- Find auto repair near me
- Troubleshoot a car problem
- Ask a 2008 Ford Taurus question
- Free Ford Taurus repair estimates
- Car care advice
Research a car
- 2008 Ford Taurus overview
- Ford Taurus reliability ratings
- Common 2008 Ford Taurus problems
- Ford Taurus Maintenance Schedule
- Find 2008 Ford Taurus recalls
- 2008 Ford Taurus owner reviews
Research a car
- 2008 Ford Taurus overview
- Ford Taurus reliability ratings
- Common 2008 Ford Taurus problems
- Ford Taurus Maintenance Schedule
- Find 2008 Ford Taurus recalls
- 2008 Ford Taurus owner reviews
More from RepairPal
- Diagnostic OBD-II codes
- Dashboard warning lights
More from RepairPal
- Diagnostic OBD-II codes
- Dashboard warning lights
See More 2008 Ford Taurus Questions
Learn About Your Car
Encyclopedia
Go to RepairPal Encyclopedia
Recent Ford Taurus Questions
- Will a 1996 Ford Taurus windshield fit a 1999 Ford Taurus?
- car will turn over but wont stay running
- My cars AC blows hot
- Why does my brake lights and taillights stop working when the lights are on
- How often do the odometer not work
2008 Ford Taurus Estimates
- Ignition Switch Replacement
($166 - $247) in Pleasanton, CA
- Window Regulator Motor Replacement
($198 - $300) in Westbury, NY
- Anti-lock Brake System Inspect
($79 - $100) in Aliso Viejo, CA
Find a Shop
- Ford Repair in West Jordan, UT
- Ford Repair in Mount Hope, WV
- Ford Repair in Spokane, WA
- Ford Repair in Knoxville, TN
- Ford Repair in Tuscaloosa, AL
- Ford Repair in Commerce City, CO