P0720: Output Speed Sensor Circuit
P0720 means Output Speed Sensor Circuit. The output speed sensor measures the speed of the transmission output shaft. The control module has detected a fault in the circuit itself, such as an open circuit, a short, or a signal outside the electrical limits it expects.
Can I keep driving? Drivable with care. Diagnose soon: performance, economy or other components can be affected.
Common symptoms
- Check engine light on
- Harsh, delayed or erratic shifts
- Limp mode
- Possibly incorrect gear display or speedometer issues
Possible causes
- Failed sensor
- Wiring or connector fault (check the transmission connector for fluid)
- Low or contaminated transmission fluid
- Misadjusted range sensor or shift linkage (range sensor codes)
How to diagnose P0720
- Check fluid level and condition.
- Inspect the transmission connector and wiring.
- Check the sensor signal on a scan tool.
- For range sensor codes, check the gear display matches the selector in each position.
What the code means, digit by digit
Generic codes have the same definition on every OBD-II vehicle (petrol cars from model year 1996 in the US, 2001 in the EU; diesels later). Manufacturers can add their own enhanced codes; those are not listed here.
Related codes
- P0725 Engine Speed Input Circuit
- P0717 Input/Turbine Speed Sensor "A" Circuit No Signal
- P0715 Input/Turbine Speed Sensor "A" Circuit
- P0713 Transmission Fluid Temperature Sensor "A" Circuit High
- P0712 Transmission Fluid Temperature Sensor "A" Circuit Low
- P0711 Transmission Fluid Temperature Sensor "A" Circuit Range/Performance
- P0710 Transmission Fluid Temperature Sensor "A" Circuit
- P0705 Transmission Range Sensor "A" Circuit (PRNDL Input)
General guidance only. Fault codes describe what the engine computer saw, not which part failed: confirm with testing before replacing parts, and follow the vehicle's service information.