Printer home position

The Y home position is not functioning. It looks like a software problem? When I (in the menu system) activate Home Position X and Z positions are OK but the Y motor pulls the head out but not back again to the home. The opto reader functions OK, tested with voltmeter. So with a number of Home-Position commands the actual Y position increases until the printer head hits the front axis. The position indicator shows 200 mm when ready, ie. home position. When using the manual control (via Repetier-Host program) I can move the head toward front, then move back until the indicator for Y-position shows 200mm. So the motor driving electronics are OK. What can be the reason for this odd behavior? Why is the home-positioning malfunctioning?? Please, anyone, give me a hint what to do!
Nils

Just a guess.

Maybe reload the firmware.

Will try! Thanks!

This behavior is quite typical of a end-stop malfunction so if reloading the firmware doesn’t solve your problem, recheck the endstop (swap the endstops or the cables).

Firmware update did not solve the problem, swapping the optical sensors did it! Probable cause: too heavy with the oil can. The Y optical sensor is a weak spot, rubber residue from the feed bands collect in the slit to the sensor. A magnetic sensor there, reed relay type? But it is probably not exact enough? I will dream on…
Thanks for the support you have given!

même problème axe y ne rentre pas a la maison , suis obligé de le faire manuellement a chaque début d impressions
firmware rechargé et pas de changement
vais nettoyer le capteur optique pour voir