Yaris Transmission Oil Pressure Sensor Fault

Sounds familiar. Had similar on my old Opel Astra. Was it the sensor itself or something else triggering it?

What was the root cause on your Astra?

Turned out the gearbox oil level was critically low. Sensor was doing its job. Would you check that before replacing the sensor?

Confirmed, oil level low. Topped up and fault cleared. 365€ at the workshop. Thanks for the tip.