Polar 78ES - upstroke movement troubles

In this machine was made a mechanical work to change the two damaged grease stoppers in the axe of the main clutch pulley. After this work the failure started to be very most frequently, the knive stops after the bottom dead center has been passed, it is beginning the upstroke movement.
Almost all related electrical causes has been checked but the failure still happens.
Any additional information is appreciated if anyone else is familiar with the problem.
The error code in the display when it happens is 603, the main of the causes listed has been reviewed.

thank you in advance

best regards

 

603


KNIFE POSITION ERROR




ERROR




addition: RED






After start of cutting or during active cut, this message is output if the positions electrical BDC
and knife pulse counter are not plausible with respect to each ot In such a case, the knife
movement is interrupted or not permitted, for safety reasons.

- Check fuse F3 of voltage supply of MHS (knife upstroke control)
- Knife upstroke control is defective
- Check correct grounding of frequency converter
- Check cable route or bus connection / knife upstroke control - SAP - CPxx
- Check / replace boards SAP, CPxx
- Check data of knife gear control or knife trace; wrong pulse values in the trac are represented
inversely
- Check mechanical play of gears
- Replace transformer TR1 on 78 ES, or, if necessary, replace entire PM unit.

 

ok...
thank you
I will try your recomendations
I will advice