Background
The index sensor is a hall effect type that is aligned at manufacturing. The problem can be a bad sensor, faulty wiring, or misalignment.
Check Wiring and USB Cable
Reason: Loose or broken wires
Check that the three wires are firmly seated in the 3-pin Molex under the motor cover. Also, check pins at the 10-pin carousel cable connector end (PN 38670). Re-seat as required.
Check your USB cable connection, as well as making sure the controller side of the USB is plugged directly into your controller.
Check Tool Tray
Reason: Tray or hub bolts came loose
Power up the mill.
With power to the ATC, you should not be able to rotate the tool tray by hand. If there is any detectable slop, make sure to tighten all six bolts that are accessible from the bottom of the tool tray.
Sensor Testing
Reason: Misaligned or bad sensor
Power up the mill.
REF the tray with control box open, and observe “IDX” indicator light for flashing. (This is a hardware light, not dependent on PathPilot.)
Attempt to realign the sensor to bring the signal back. The marker dot on the Molex should face the hub of the ATC. Turn the Molex one to two full turns up, then one to two full turns down. At each turn, rotate and check for an LED flash.
Board Issue
Reason: Bad ATC board
Check for 68 DCv on your board. (Wires 204-205)
If the sensor appears to be functioning, you have voltage on your board, and you need to realign your ATC after an emergency stop, or powering down your machine, contact Tormach Technical Support.