P0721
Output Speed Sensor Range/Performance
Generic code
Transmission System
High severity
Hard repair
Free on OBD DashX
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What P0721 means
- The fault code P0721 indicates that there is a problem with the output speed sensor circuit. This may cause issues with the transmission shifting and could potentially lead to damage to the transmission if left unattended.
Possible symptoms
- Incorrect gear ratios
- Harsh or delayed shifting
- Transmission slipping or overheating
- Illuminated check engine light
Possible causes
- Failed output speed sensor
- Faulty wiring or connections in the circuit
- Loose or corroded electrical connections
- Failed transmission control module (TCM)
Related parts
- Output Speed Sensor: The output shaft connects the wheels to the gearbox. Output speed sensor monitors the speed at which the output shaft is rotating. This car's malfunctioning sensor will lead to reduced performance & poor acceleration
Possible solutions
- Replace the output speed sensor
- Check and repair any damaged wiring or connections
- Tighten or clean any loose or corroded electrical connections
- Replace the transmission control module (TCM) if necessary
Free on OBD DashX
P0721 on OBD DashX
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