P0722 — Output Speed Sensor Circuit No Signal
Moderate severityWhat it means
P0722 is stored when the engine control unit sees a fault involving the output speed sensor circuit. The output speed sensor measures the transmission's output shaft speed (vehicle speed); the control unit uses it for shift timing and the speedometer. “No signal” means the speed/position signal disappeared entirely, so the control unit has nothing to work with from this sensor.
Common symptoms
- A reading that drops to zero while moving
- Speedometer dead or erratic
- Harsh or wrong-timed shifts
- Limp mode in some cases
Likely causes
- A dead sensor or a broken signal wire
- A damaged tone/reluctor ring
- Faulty output speed sensor
- Wiring/connector fault at the transmission
What to check first
- Watch the live value while driving and check the sensor wiring and tone ring
- Compare output speed in live data with actual/GPS speed
- Inspect the sensor connector and wiring
Can you keep driving?
Drivable with care, but shifting and the speedometer may misbehave; diagnose soon.
Frequently asked questions
What is the most common cause of P0722?
The most likely cause is: A dead sensor or a broken signal wire. Several other faults can set P0722 as well, so confirm the real cause with live data and the checks above before replacing any parts.
Can I just clear P0722 and keep driving?
Clearing P0722 with an OBD2 scanner turns the warning light off, but if the underlying fault has not been repaired the code will usually come back within a few drive cycles. Fix the cause first, then clear the code to confirm the repair worked.
How serious is P0722?
P0722 is a moderate-severity code. The car is often still drivable, but have it diagnosed soon — the underlying problem can get worse and it may fail an emissions test.
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