Steer controller position sensor help – Special Instructions

Hi, I'm checking a Weiler S450 (Caterpillar 545D) with error codes 4694-14 and 1694-14. I checked the magnetic sensor in the steer joystick and it looks ok, in screen the universal joystick have a range between -86.1% (Left) and 100% Right, so I think I have to calibrate the joystick, I worked before with John Deere forestry machinery, so I don't have ET to check with my computer. I checked the REHS0126 special instruction to understand better the CAT codes system, and the 14 FMI mention that I need a special instruccion to solve that problem. I tried to find out with google but I can't find the error code, any ideas? Thank you very much and sorry for my English