Error Code Error 20
Bosch washing machine
Error Code: Error 20 (Bosch/Siemens Washing Machines)
Appliance Type: Washing Machine
Brands: Bosch, Siemens
Description of Error: Error Code 20 specifically indicates a failure in the turbidity sensor calibration process. The turbidity sensor (often referred to as the optical sensor) is critical for modern washing cycles as it measures the cloudiness or dirt level of the water during the wash phase. This measurement allows the machine’s electronic control unit (ECU) to dynamically adjust the water usage, rinse times, and detergent dispensing for optimal cleaning efficiency. When the system attempts to calibrate this sensor during startup or a specific cycle phase and fails, Error 20 is displayed.
Recommended Troubleshooting Steps:
Initial Reset Procedure:
- Action: Try restarting the washing machine.
- Detail: A temporary glitch or momentary fluctuation in the electronic control system can sometimes prevent the calibration sequence from completing successfully. Perform a full power cycle by turning the appliance off using the main power switch or unplugging the machine from the wall socket for at least five minutes. This allows any residual charge in the system capacitors to dissipate, forcing a complete electronic reboot upon reconnection. After waiting, plug the machine back in, turn it on, and attempt to start a short program to see if the error has cleared.
Escalation (If Error Persists):
- Action: If the error persists after attempting a full restart, please contact a specialist.
- Detail: Since Error 20 points directly to a calibration failure of a specific internal component (the turbidity sensor or its associated wiring/control board connection), user intervention beyond a simple restart is often limited. Continued recurrence suggests a hardware issue, such as a faulty turbidity sensor unit itself, damaged connecting ribbon cables, or an issue with the main control board responsible for executing the calibration routine. Do not attempt to access internal components unless you are a qualified technician, as working with internal electronics poses a risk of electric shock and further damage to the appliance. Contact an authorized Bosch or Siemens service technician for professional diagnosis and repair.
