Haas TL-1 Z-axis homing issue

Machine was built in 2002. I have owned it since 2007. This machine gets lightly used, I probably use it 200 hrs/yr. Today I fired it up like normal and during the homing cycle I noticed the Z axis moving in the incorrect direction. It moves towards the spindle. I have opened up the back cabinet, breakers don't seem to be the issue and I do not see any faults or blinking lights. I've tried shutting it down and restarting it after 5 min many times. The Z-axis limit switch is mechanically working properly. Any Ideas what the issue could be? Here is a video.

20150126 190240 - YouTube

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Originally Posted by rideredcr

The Z-axis limit switch is mechanically working properly. Any Ideas what the issue could be?

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It's working mechanically, but is it working electrically? Meaning can you see it change states in diagnostics?
The issue you are describing typically points to a faulty switch.

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Originally Posted by haastec

It's working mechanically, but is it working electrically? Meaning can you see it change states in diagnostics?
The issue you are describing typically points to a faulty switch.

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Thank you for your quick response haastec. I will verify if the z axis limit switch is working electrically and post my results.

I had this problem was when getting chips on the sensor zero position z.

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Originally Posted by andre_77

I had this problem was when getting chips on the sensor zero position z.

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Haastec was correct. It was the Z - axis limit switch. The switch had high resistance. Further inspection showed coolant had seeped down inside it. With as much coolant drained out of switch as possible (it is a solid molded switch), the lathe functions properly now. Big thank you to Haastec