Bosch Dryer Error Code E:8031

Error code E:8031 on a Bosch dryer indicates a fault within the door sensor or door switch circuit. This code is the 4-digit equivalent of E:16 and is triggered when the control board detects an unexpected door state during an active drying cycle. The door switch is a critical safety component that communicates to the control board whether the door is securely closed. When the board receives a signal suggesting the door has opened, or when the switch itself sends an inconsistent or absent signal, the machine halts operation and logs this fault.

The most common underlying causes fall into two categories: a physical issue with the door switch or sensor, or an electrical connectivity problem in the circuit connecting the switch to the control board. The door switch can fail mechanically due to repeated use, causing internal contacts to wear out or break. Alternatively, the wiring harness leading to the switch can develop loose connectors, corroded terminals, or broken wires, all of which interrupt the signal. The fault can also be triggered if a connected window or access panel was opened while the dryer was running, which the control board interprets as a door-open event.

The first diagnostic step is to inspect all electrical connections at the door switch and along the associated wiring harness. Connectors should be seated fully and terminals should show no signs of corrosion or heat damage. If connections appear sound, the switch itself should be tested for continuity using a multimeter. A properly functioning door switch will show continuity when the door is closed and an open circuit when the door is open. A switch that fails to change state correctly, or reads no continuity in either position, requires replacement.