Coolant Pump Won't Run

Background

The coolant systems are controlled with the following G-code (M-code) commands:

• M08 (flood)

• M09 (deactivate all coolant)

When PathPilot identifies those commands it causes a component on the control board to power, or remove power, to the coolant pump.

Tools

• Digital multimeter

• Screw Driver

• Box Wrench or Crescent Wrench

Reseat the coolant pump power cord

Reason: The coolant pump isn't plugged in to an outlet.

1. Unplug and reseat the coolant pump power cord.

Inspect the coolant pump strapping

Reason: The coolant pump isn't strapped for your machine power.

Open the box on the side of your pump. Check the strapping compared to the diagram on your pump.

Inspect fuse F10

Reason: Fuse F10 is blown

1. Power off the machine.

2. Locate and remove the F10

3. Measure the resistance across the fuse with digital multimeter set to resistance.

   1. Replace the fuse if the digital multimeter reads OL, shows a resistance in the MΩ, and/or doesn’t produce continuity tone.

   2. If the fuse measure 0-5 Ω, reinstall it.

Inspect the coolant pump

Reason: The coolant pump is damaged.

1. Unplug the coolant pump power cord from the machine and examine it for damage.

2. Test the coolant pump by:

   1. If possible, plug it into a known good outlet to see if it turns on.

   2. Use a digital multimeter to verify the motor’s resistances from winding-to-winding and winding-to-ground. If any winding-to-winding resistance measurement is a short (near zero resistance), an open circuit, or if the winding-to-ground resistance is a short, the coolant pump must be replaced.