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OmniTurn G3 CNC:
No yellow "Control On" lamp or no display on monitor



NOTE: Blue text links to pictures; click picture to close.

Oregon Coast (Click picture to close)
No yellow "Control On" lamp:
The yellow power light indicates that the computer power supply is working. The 12V should come on when the system is turned on and the computer power supply is working.
If the monitor displays the start-up information, replace the bulb (#53 bayonet).

Rotate locking lever to access bulb.
If there is also no display on the monitor, first do the following:
Located on the left side of the GT75.
Located on the back of the GT75. Worklamp power cord also plugs in here.
Located on the back of the CNC control.
Located in the spindle-drive cabinet.
Located in CNC, on on back panel.
Fan is ON: If the fan is on, the Control On lamp may have blown and not been replaced, and the monitor might also be bad. Or the computer power supply may have failed. If the issue is a bad monitor, the control will boot up as normal, but there will be no display on the monitor.

To quickly determine if it’s just the monitor, set power on, then wait a minute for the computer to boot up, then press the "Caps Lock" key and see if the "Caps Lock" light goes on. If it does, click here to troubleshoot the monitor.

If the "Caps Lock" light does not come on when you press the key, do the following to check the computer power supply:

If you do read between 11.5 and 12.5 volts DC:
Computer power supply connector.
Located in CNC on connect card.
Connect Card.
Fan is NOT ON: If the fan is not on, but the fuses check good, the Control On switch may be defective, or disconnected.

To verify that the Control On switch is properly connected, first set control power OFF, then check the following:

Located in CNC on connect card.
Connect Card.
TS1 wires at switches.
If TS1 and wires to switches look good, do this:
Check 110VAC at Control On.
For reference, front panel wiring schematic is available here.

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