Without looking or sitting on the tractor I can't remember but pull the range lever back to neutral and repeat will calibrate the other 2 clutches. Perhaps this only works for quad mod?This will calibrate clutch packs C3 and C4. As I remember C1 and C2 are done automatically in use. Think they can be done manually but you need a ''special'' switch plugged in to the wiring harness at the fuse box and have to go into diagnostic mode for that!
Get the transmission up to operating temperature. A bit of use for half an hour or so. Switch off engine,handbrake on and air con,blower etc off. Clutch down and hold both powershift buttons in together.Start engine and CAL should show on display on dash.Release buttons and push the 3 gearshift levers forward. Let clutch up.Tractor should not move.Set revs to 1200rpm. Hold in the upshift button and calibration will begin for C3.You'll see a 3 digit number which will increase one digit every second until the engine revs drops by 50 revs. When the number remains steady,that's it for that clutch pack. Hold in the downshift button then,and the numbers will reappear low and climb as before.When steady,that's C4 calibrated. When done,just stop the engine and when you restart CAL should be off the screen.
BTW,I'd really recommend you get a workshop manual for the 40 series but make sure it covers the early prequad transmission that you have. (It likely will anyway). It's inevitable that error codes will be a part of life...!