Carpet cleaner powers on but brush motor does not run; suction motor may still operate

Safety first: Disconnect the Bosch carpet cleaner from mains before opening any covers.

• 1. Confirm symptom
  • Switch the unit on and select a cleaning mode that should spin the brushes.
  • Verify that suction is present but the brush roll does not rotate.
• 2. Inspect brush area for jams
  • Remove the brush access cover (usually on the underside of the cleaning head).
  • Clear hair, threads, and debris from the brush roll and end caps.
  • Try rotating the brush by hand; it should turn freely with slight resistance.
• 3. Check motor wiring harness
  • Access the brush motor compartment in the floor nozzle or base.
  • Inspect the Bosch wiring harness connector for loose pins, corrosion, or heat damage.
  • Reseat the connector firmly; repair or replace damaged wires.
• 4. Test brush motor
  • Disconnect the motor from the harness.
  • Use a multimeter to measure resistance across the motor terminals; an open circuit indicates a failed motor or internal thermal fuse.
  • If accessible, check the inline thermal fuse on the motor; replace the motor assembly if the fuse is non-serviceable.
• 5. Check control PCB output
  • If the motor tests good, the control PCB may not be sending voltage to the brush motor relay.
  • This requires live testing and should be done only by a qualified technician; if no output is present, replace the main control PCB.