Vacuum runs only at low power or surges; error E5 appears intermittently

Safety first: Remove the battery pack before any disassembly.

• External cleaning: Blow out dust from around the motor housing and vents using dry compressed air. Avoid directing high-pressure air directly into bearings.
• Check for pattern: Note if E5 occurs only at high power settings or under heavy load. If so, reduce load and verify if the vacuum operates normally at lower settings.
• Inspect wiring (if accessible): If the model allows access to the motor compartment without fully dismantling, check for loose or pinched wires between the motor and PCB.
• Do not lubricate sensor: Do not apply oil or spray cleaners near the motor sensor area; this can worsen sensor readings.
• Professional repair: A defective Hall sensor or speed-control circuit requires motor or PCB replacement. Have the unit serviced by Hilti to replace the motor assembly or control board.