What is a transmission speed sensor?
A vehicle’s transmission speed sensors monitor the rotational speed of a manual or automatic transmission. It then relays this information to a transmission control unit (TCU) so that it can smoothly shift gears at the appropriate times.
Without a properly working transmission speed sensor, you’ll likely experience rough gear shifting that could make your car undrivable or cause expensive damage.
When should I replace the transmission speed sensor on my car?
The transmission speed sensor doesn’t typically come with regular maintenance or replacement intervals—you’ll only need to replace it if it’s not working properly. A certified mechanic can inspect your vehicle and determine whether or not you need a transmission speed sensor replacement.
The most common symptoms of a bad transmission speed sensor include:
Rough gear shifting: If your transmission control unit can’t communicate with your transmission speed sensor, it will become more difficult for your vehicle to switch gears as your speed changes—which can lead to a jerking, uncomfortable ride.
Check engine light turns on: If your vehicle’s onboard diagnostic (OBD) system detects a problem with your transmission speed sensor or related part, your check engine light might turn on as a result.
Cruise control won’t work: Your cruise control depends on information from the transmission speed sensor to maintain a constant speed. If your transmission speed sensor fails, you might notice that your cruise control no longer works properly.
Inconsistent RPM or speedometer readings: The RPM gauge on your dashboard also depends on information from the transmission speed sensor. If your RPM readings are erratic or don’t seem to be consistent with your vehicle’s actual operating conditions, it’s possible a bad transmission speed sensor could be the culprit.
How often should a transmission speed sensor be replaced?
Transmission speed sensors don’t typically require routine maintenance or replacement unless they fail prematurely. A certified mechanic can inspect your vehicle to determine whether or not your transmission speed sensor is working properly.
Can I replace my transmission speed sensor myself?
A transmission speed sensor replacement is a job best left to the professionals. It can be a difficult part to access on many vehicles, and a mechanic should inspect your vehicle to identify any other potential problems that could have similar symptoms.