how often the optical sensor goes bad on

how often the optical sensor goes bad on the CS-400E machines

2017/3/1 1:22:43

Does anyone know how often the optical sensor goes bad on the CS-400E machines. I have 2 machines and it seems that the optical correction does not work anymore. I keep getting an optical correction error, when the mode is turned on the correction does not see the PTH and says to recenter. I was wondering if anyone else out there has had this problem or knowledge of the failure rate of these optical sensors.

Thanks