Fanuc 6MB Tool position is resetting to #1

[moldmker]

Machine: Kitamura Mycenter 2 VMC (umbrella style tool changer)
Control : Fanuc 6MB

Problem:

Occasionally, the control will reset the current tool to #1 at program start.
Usually happens on first run after power-up but will occasionally occur after several hours of running (but always at prog. start).
I can reset to the correct number via the parameter page.

Obviously this is only noticed when running a prog. that starts with something other than T1.

I have been running the same program for the past 2 weeks. It has an air blast in it that does throw chips into the tool carousel.

Just reading my diagrams, I don't see any type of carousel position feedback, might there be something in the servomotor that I should look at?

Any boards I should investigate?

Thanks,
Bob

[moldmker]

I think I answered my own question...

While cleaning the machine today, I was able to see above the tool carousel.
I spotted a prox sensor reading the rotations of the indexing motor. It was polluted with aluminum chips.

All clean now.