Onix temperature sensor issues

That's a weird combo of issues for a single sensor fault! Are you sure it's just the outside temperature sensor? It almost sounds like a CAN bus problem affecting multiple systems, like a power surge fried multiple circuits. Have you checked the sensor calibration? And where is the sensor located on your Onix?

CAN bus fault is a bit extreme, I hope not. Sensor calibration wouldn't cause frozen washer jets, would it? As for location, the sensor's behind the front bumper, drivers side. Reason I ask about the cable is the bumper took a slight knock there a while back (parking mishap!). Worth a look you think?

Ok, that location makes sense given your parking incident. Definitely inspect the wiring and connector first. If the impact damaged the wires even slightly, that could explain the wonky readings or complete failure. Still, the A/C thing is odd. If checking the wiring doesn't solve it, a workshop might need to dive deeper. They can perform advanced sensor checks to see if they're sending proper signals to the computer.

Cheers for the advice. It was indeed the cable, chafed right through where it runs behind the bumper. Replaced the damaged section and all's well - air con's blasting, mirrors are toasty, and the washer jets are firing! Total cost was 95€ including the cable.