FM-21: Sander cuts out repeatedly under ordinary load

The tool runs at no load but repeatedly shuts off during normal light sanding.

• Battery protection opens under load
• Contacts or battery are weak
• Vents are blocked or tool is overheated
• Pad/drive friction or controller fault

1. The sander runs continuously under ordinary light sanding load.

1. Set O, remove the battery, let both cool, and clear every external vent.
2. Verify free pad motion, a fresh disc, light pressure, and an unobstructed dust path.
3. Repeat a short test with a known-good charged battery.
4. If cutout returns under ordinary load, stop and use authorized service.

This is a preview of the troubleshooting guidance included in the full repair manual.

• Terminal contacts
• Brushless motor and fan

• Sander cuts out repeatedly under ordinary load

  The tool runs at no load but repeatedly shuts off during normal light sanding.

• root cause analysis
• tools needed
• step-by-step repair procedure
• diagrams
• exploded views
• post-repair checks

Public pages show a preview only. Purchase the full manual to download complete repair steps, diagrams, and verification procedures.