Cost efficient method for communicating from an appliance to an external device

A method for diagnosing a household appliance comprising a user interface including a plurality of visible light-emitting indicators and a processor, the method comprising the steps of:

• conveying, by the plurality of visible light-emitting indicators, primary operational information indicative of an operational aspect of the household appliance to a user during a normal operation of the household appliance;
• obtaining, by the processor, an error condition during an operation of the household appliance;
• determining, by the processor, an error code corresponding to the error condition;
• waiting to detect a door switch actuation sequence on the household appliance to start a two-way communication;
• causing, by the processor, the plurality of visible light-emitting indicators to transmit the error code to an external device based on the two-way communication;
• interpreting the error code, by the external device;
• and
• communicating between the household appliance and the external device regarding the user diagnostics data corresponding to the error code,
• wherein the plurality of visible light-emitting indicators are configured for the two-way communication between the household appliance and the external device by the plurality of visible light-emitting indicators receiving control signals from the external device.