I had the same a couple of years back. Turned out to be a beak in the circuit where the fuelling mod was connected.

If the error 22 is showing the ECU is receiving NO signal from the AIT sensor which means either the sensor has gone bad (unlikely) or there's a wiring fault. If the bike has been laid up, then it's likely to be a corroded or bad connection. Check the wiring and your solder joints. Also check the resistance of the Kev mod with a multimeter, making sure it changes smoothly as you twist the dial.

The bike is safe to run. The fail safe action is for the ECU is to fix the air temperature to 20C. The bikes may run a bit weak if the ambient temperatures are very low, but you'll be fine for a short while until you fix it.

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