A transmission warning and P0722 can send an owner searching for a speed sensor, conductor plate or complete TCU. Before choosing a part, establish what the scan actually recorded and which transmission is fitted.
The signal the controller is missing
iCarsoft describes P0722 as an output-shaft speed-sensor circuit with no signal received by the transmission or engine controller. Its technical explanation connects that information with shift control and notes that wiring, sensing and controller issues need to be distinguished. Read iCarsoft’s P0722 explanation.
The component layout and test procedure remain vehicle-specific. A code definition does not establish whether the sensor is separately replaceable or integrated into an assembly on your gearbox.
Build a report that can be used twice
Save the complete diagnostic report before clearing anything. Include the selected gear, observed vehicle behaviour and whether the code is current or intermittent. If a garage has recorded speed data, ask it to label the input and output channels and describe the test conditions.
Also include the transmission part number or identification and any recent gearbox, wiring or module work. A clear report lets a second technician understand the first technician’s findings without repeating every step.
Sending a module or booking the vehicle
Do not remove a controller solely because a search result associates it with P0722. Ask what has been established about the signal path and what further testing is required. A vehicle that loses drive or behaves unpredictably may need recovery rather than continued use.
Ask AXION about transmission-electronics assessment. Suitable postal jobs are agreed individually for UK owners and garages; complete-vehicle diagnosis requires an arranged workshop visit.
Reviewed September 2026. Use the complete manufacturer-specific fault description and vehicle repair information.