3845

Common Causes

• Coolant tank level actually low from evaporation, carry-off on chips, or leaks
• Float switch stuck or positioned too high so it reads low before the tank is truly empty
• Failed float switch or wiring fault on the iCOLLO/ input

Troubleshooting Steps

1. 1Read the code number shown with the alarm: code 1 = The coolant low-level input (I/O check NO.36 INPUT bit 6, iCOLLO/) has been OFF continuously for 1 second or more.
2. 2Top up the coolant tank to the correct level and check for leaks at hoses, pumps, and the machine bed that are draining the tank.
3. 3Open I/O check NO.36 and watch INPUT bit 6 (iCOLLO/): with the tank full it should change state; if it stays OFF the float switch is not responding.
4. 4Lift the float by hand and confirm the input bit toggles; if it does not, check the float switch wiring and connector for coolant contamination or damage.
5. 5Verify the float switch mounting height so it switches at the intended low level, not prematurely.
6. 6If the wiring and input are good but the switch never changes state, replace the float switch.