Probable causes: faulty battery connection, internal tool damage, or a mechanical obstruction.
Fix sequence:
- Remove and re-insert the battery cartridge. Ensure it is inserted all the way until the red indicator on the button cannot be seen.
- Check that the forward/reverse selector is fully engaged in either the forward or reverse position, not stuck in between.
- Inspect the chuck and drill bit. Remove any bit and operate the tool. If noise stops, the bit or its installation was the issue.
If that didn't work, the battery may be damaged or non-compliant. Use only specified Makita battery cartridges: BL1815N, BL1820B, BL1830, BL1830B, BL1840B, BL1850B, BL1860B. Try a different battery.
If the problem persists with a known-good battery, the tool likely has internal damage. Stop use. Have it serviced by a qualified repair person using genuine Makita parts.