Vacuum does not start; LED flashes in an E3 pattern immediately when trigger is pulled, even with a charged battery.

Safety first: Remove the battery from the vacuum before inspection. Do not attempt to open the battery pack.

• Verify battery type: Ensure you are using a genuine Makita Li‑ion battery of the correct series (e.g., 18V LXT, 40Vmax XGT) specified for your cordless vacuum model.
• Check battery charge: Press the battery fuel gauge button (if equipped). If only one or no LEDs light, fully charge the battery using a Makita charger before retrying.
• Inspect terminals: Examine the battery and tool terminals for corrosion, dust, or deformation. Clean gently with a dry cloth. Do not use liquids or abrasives.
• Try another battery: If available, test the vacuum with a different known-good Makita battery. If the vacuum runs normally, the original battery is likely faulty.
• If E3 persists with multiple batteries: The vacuum’s control PCB or voltage-sense circuit may be defective. Disassembly beyond the battery compartment should be done only by a qualified technician.