Cordless vacuum will not start at all; no lights, no sound, even with multiple batteries.

Safety first: Remove the battery. Do not attempt to bypass fuses.

• Verify batteries: Confirm that the batteries work on other Ryobi ONE+ tools.
• Inspect battery slot: Look for loose or recessed terminals. If they move excessively, internal solder joints may be broken.
• Check for physical damage: Look for cracks or heavy impact marks on the handle or body that could have broken internal wiring.
• Advanced users: If you are experienced with electronics, you may open the housing to visually inspect the control board for burned components or blown fuses, but replacement should be done by a professional.

Complete power failures almost always require control board or wiring harness replacement by a technician.