Unusual chemical or plastic smell from the vacuum even when not in use.

Safety first: If the smell is strong or acrid, do not use the vacuum until inspected.

• Inspect for discoloration: Look at vents and housing for yellowing or warping that indicates heat damage.
• Check battery: Remove the battery and inspect for swelling, cracks, or leakage. Do not use a damaged battery; replace it immediately.
• Ventilate: Place the vacuum in a well-ventilated area for 24 hours and recheck. Mild new-plastic smells often fade.
• If smell persists or worsens during use: Have the motor housing and PCB inspected by a Makita service center for heat damage.