What does a VSS speed sensor do?
What does a VSS speed sensor do?
The vehicle speed sensor (VSS) measures transmission/transaxle output or wheel speed. The ECM uses this information to modify engine functions such as ignition timing, air/fuel ratio, transmission shift points, and to initiate diagnostic routines.
How is the vehicle speed sensor ( VSS ) used?
As you can probably guess, the vehicle speed sensor (VSS) is used to determine vehicle speed. This information is used by various ECUs throughout the vehicle, including the PCM and TCM. The PCM uses the VSS signal to determine the control of outputs such as EGR function and speedometer operation.
What happens when the transmission speed sensor is lost?
If the signals are lost from the transmission speed sensors, the PCM will set a DTC and illuminate the Check Engine Light on the vehicle dashboard. It also can indicate an increase in tailpipe emissions surpassing acceptable limits for environmental contaminants from motor vehicles.
Can a bad speed sensor affect shift timing?
Harsh or improper shifting. Without a valid speed signal from these sensors, the PCM will not be able to correctly control the shifting of gears within the transmission. This may cause the transmission to shift roughly or more quickly than normal. It’s also common that a problem with these sensors can impact the shift timing,…
Where are the speed sensors on a car?
The VSS is connected to a speedometer cable and positioned between the axle and the wheel of a vehicle. The most common types of VSS operate from a magnet connected at the back of the transmission housing behind the speedometer. The top of the VSS senses the output of the transmission.
What happens if the VSS sensor is not working?
Vehicle speed information relayed by the VSS is used by the transmission control module (TCM) or powertrain control module (PCM) to determine shift timing. Therefore, a failing speed sensor will have a direct impact on automatic transmission operation.
Where is my vehicle speed sensor ( VSS ) wire located for?
Where is my Vehicle Speed Sensor (VSS) Wire Located for Radio Installation? When you remove your OEM radio, there are 4 plugs that plug into the radio. Only 2 of the 4 connectors are used with your new aftermarket radio which are the 2 connectors with the larger size pins.
What are the symptoms of a bad speed sensor?
A faulty speed sensor can affect your speedometer operation and reduce your ability to drive safely. 5 Common Bad Speed Sensor Symptoms. Transmission problems. Vehicle speed information relayed by the VSS is used by the transmission control module (TCM) or powertrain control module (PCM) to determine shift timing.
How does the transmission speed sensor work in a car?
A car’s transmission speed sensor, sometimes called a vehicle speed sensor (VSS), works out how quickly it’s moving along the road. When you look down at your car’s speedometer, the figure you see is communicated from this little component. Your vehicle depends on the transmission speed sensor to function correctly.
