Dishwasher shows A12; may be associated with communication or configuration issues between modules.

Safety first: Disconnect power.

• Power reset: Leave the dishwasher unplugged or power off at the breaker for at least 10 minutes to allow the electronics to fully discharge. Restore power and test.
• Check display and buttons: Ensure all buttons respond and the display is not flickering or missing segments, which may indicate a user interface board issue.
• Inspect wiring: Remove the inner door panel and check the harness between the user interface and the main control board for loose connectors or damage.
• Look for signs of board damage: On the main PCB (usually in a plastic housing at the base), look for burnt components, corrosion, or water ingress.

Control board or UI replacement is often required for A12 faults and is best performed by a qualified technician due to the need for correct configuration and safety checks.