Sensors are critical components in modern AEG appliances. They monitor temperature, humidity, water levels, drum speed, and door lock status. When a sensor fails, the appliance may display an error code, stop mid-cycle, or operate inefficiently. This guide explains how to inspect sensors on AEG washing machines, dryers, dishwashers, ovens, and fridges sold in Spain. We cover common sensor types, location, visual inspection, multimeter testing, and typical error codes. Always disconnect power before any inspection. For complex repairs, refer to our complete guide to AEG appliance repair in Spain.

Why Sensor Inspection Matters

Sensors provide real-time data to the control board. A faulty sensor can cause:

  • Incorrect water temperature (e.g., washing machine not heating)
  • Overfilling or underfilling
  • Drum not spinning or erratic spin
  • Dryer not drying or overheating
  • Dishwasher not cleaning properly
  • Oven temperature fluctuations
  • Fridge or freezer not cooling

In Spain, where energy costs average €0.15/kWh (2024), a faulty sensor can increase electricity bills by 20-30%. Regular inspection can save money and extend appliance life.

Tools Needed for Sensor Inspection

  • Screwdrivers (Phillips and Torx T20/T25)
  • Multimeter with resistance and continuity modes
  • Needle-nose pliers
  • Flashlight
  • Safety gloves
  • Replacement sensor (if needed) – available at AEG service centers or online retailers like Amazon.es, MediaMarkt, or El Corte Inglés. Prices range from €15 to €60.

Inspecting Sensors on AEG Washing Machines

AEG washing machines use several sensors: NTC thermistor for temperature, pressure switch for water level, Hall sensor for motor speed, and door lock switch. Common error codes include E10 (water inlet issue), E20 (drain problem), and F11 (drum motor fault). See AEG washing machine error codes for a full list.

Temperature Sensor (NTC Thermistor)

The NTC thermistor is located near the heating element at the bottom of the drum. To inspect:

  1. Unplug the machine and remove the back panel (two screws at top, four at bottom).
  2. Locate the thermistor – a small plastic component with two wires, clipped into the heater housing.
  3. Disconnect the wiring connector.
  4. Set multimeter to resistance mode (kΩ).
  5. Measure across the two terminals. At room temperature (20°C), typical resistance is 5-6 kΩ. At 30°C, it drops to 3-4 kΩ.
  6. If resistance is infinite (open circuit) or zero (short circuit), replace the thermistor. A new NTC costs about €20-30.

Pressure Switch (Water Level Sensor)

The pressure switch is a round plastic disc with a hose attached, usually on the top right side of the machine. It detects water level via air pressure.

  1. Remove the top panel (two screws at the back).
  2. Check the hose for cracks or blockages – clean with a thin wire if needed.
  3. Disconnect the electrical connector.
  4. Use a multimeter to test continuity between common and normally open (NO) terminals. When you blow into the hose, the switch should click and show continuity.
  5. If no continuity or if the switch is stuck, replace it (€25-40).

Hall Sensor (Motor Speed Sensor)

The Hall sensor is mounted on the motor. It sends pulses to the control board to regulate spin speed. If faulty, the machine may not spin or show error F11. See AEG error code F11 for details.

  1. Remove the back panel and locate the motor (large cylindrical component).
  2. The Hall sensor is a small plastic part with three wires, attached to the motor casing.
  3. Disconnect the wiring harness.
  4. Spin the motor pulley by hand while measuring voltage between signal and ground (DC 5V). A healthy sensor produces a fluctuating voltage (0-5V).
  5. If no fluctuation, replace the Hall sensor (€30-50).

Inspecting Sensors on AEG Dryers

AEG dryers (including heat pump models) use NTC thermistors for temperature, moisture sensors in the drum, and door switch sensors. Common errors: E61 (heating issue) and E64 (moisture sensor fault). Check AEG dryer error codes for more.

Moisture Sensors

Moisture sensors are two metal strips (or bars) inside the drum, usually near the lint filter. They measure conductivity to detect dampness.

  1. Unplug the dryer and open the door.
  2. Locate the metal strips – they may be covered with lint. Clean them with a damp cloth and fine sandpaper if corroded.
  3. Disconnect the wiring from the sensor (under the top panel).
  4. Measure resistance between the two terminals. When dry, resistance should be high (MΩ). When moistened with a wet finger, resistance should drop to 1-10 kΩ.
  5. If no change, replace the sensor assembly (€20-35).

Thermistor (NTC) in Dryer

Located near the heater element (or heat pump unit). Test resistance as described for washing machine NTC. Typical values: 10-12 kΩ at 20°C. Replace if out of range (€15-25).

Inspecting Sensors on AEG Dishwashers

AEG dishwashers have NTC thermistors, flow meters, turbidity sensors, and door latch switches. Error codes like E15 (water leak) and E24 (drain issue) may involve sensors. See AEG dishwasher error codes.

Flow Meter

The flow meter measures water intake. It is a small plastic device with a spinning impeller, located where the inlet hose connects to the dishwasher.

  1. Remove the lower front panel (kickplate).
  2. Locate the flow meter – often transparent with a wire connector.
  3. Disconnect the wires.
  4. Set multimeter to continuity. Spin the impeller gently; you should hear a clicking sound and see continuity pulse.
  5. If no pulse, replace the flow meter (€25-40).

Turbidity Sensor

This sensor detects how dirty the water is, adjusting cycle duration. It is located in the sump area.

  1. Remove the bottom spray arm and filter assembly.
  2. The turbidity sensor is a small black or white component with a lens. Clean the lens with a soft brush and mild detergent.
  3. Test with multimeter: typical resistance between signal and ground is 10-50 kΩ depending on water clarity.
  4. If readings are erratic, replace the sensor (€30-50).

Inspecting Sensors on AEG Ovens and Hobs

Ovens use NTC temperature sensors and door lock switches. Hobs have touch sensors and temperature limiters. See AEG oven error codes.

Oven Temperature Sensor (NTC)

Located inside the oven cavity, usually at the back. To test:

  1. Disconnect power and remove the oven back panel (if accessible) or the sensor from inside.
  2. Measure resistance at room temperature: around 1 kΩ (for PT1000 sensors) or 10 kΩ (for NTC).
  3. Heat the sensor with a hairdryer – resistance should decrease (NTC) or increase (PT1000).
  4. If no change, replace (€20-40).

Inspecting Sensors on AEG Fridges and Freezers

Fridges use NTC air sensors, defrost sensors, and door switches. Error codes like E10 (fridge sensor) or E20 (freezer sensor) indicate faults. See AEG fridge error codes.

Air Temperature Sensor

Located behind the rear panel inside the fridge compartment. To test:

  1. Unplug the fridge and remove the rear panel (screws or clips).
  2. Disconnect the sensor connector.
  3. Measure resistance at 0°C (ice water) – should be around 10-12 kΩ for NTC. At 20°C, 5-6 kΩ.
  4. Replace if open or short (€15-30).

When to Call a Technician in Spain

If sensor inspection does not resolve the issue, or if you are uncomfortable with electrical testing, contact a professional. In Spain, AEG authorized service centers charge a call-out fee of €50-90 plus parts. For complex control board faults, see when to call a technician for AEG appliances.

Related articles