Hi. 83 code refers that hte pot of the throttle is out of neutral point. it should be around 2.5 V and that is why the learning is failing. You can manually adjust the pot (it has some gears attached to it that you can manually adjust) in order to have the 2.5 V. You can check the voltage in the display-service menu, or you can measure it directly on the pot connector. I hope this help.

best regards