Carpet cleaner runs briefly then stops; E3 appears and the unit beeps; solution spray may not activate.

Safety first: Disconnect the appliance from mains power before servicing.

• Check solution tank and filter: Remove the clean water/solution tank. Ensure it is filled and properly seated. Inspect any inlet filter or mesh screen at the tank outlet and rinse under warm water to remove detergent residue.
• Inspect spray nozzles: Remove the floor nozzle and check the spray jets for clogs. Soak them in warm water with a little white vinegar to dissolve mineral deposits, then flush thoroughly.
• Bleed air from the pump: Refit the tank, fill with warm water only, and run the unit for 30–60 seconds (if it will run) to purge air from the pump. Intermittent E3 can be caused by air-lock.
• Check pump wiring: Access the internal pump (usually near the base). Inspect the wiring harness and connectors for loose plugs or corrosion. Reseat all connectors firmly.
• Test pump resistance: With the pump disconnected, measure coil resistance with a multimeter. Compare to AEG specifications; an open circuit or very low resistance indicates a failed pump.

If the pump is seized (buzzes but does not move water) or tests faulty, replace the complete solution pump assembly.