Bunn digital brewer shows E09; unit may not power up fully or may randomly reset.

Safety: Unplug the brewer before inspecting electrical connections. If you suspect building wiring issues, consult an electrician.

Steps:

• 1. Verify outlet voltage: Use a multimeter to confirm correct line voltage at the outlet (e.g., ~120 V AC in North America). Avoid using long, undersized extension cords.
• 2. Inspect power cord: Check the Bunn power cord for cuts, burns, or loose prongs. Replace if damaged.
• 3. Check internal connections: Remove the access panel and inspect line, neutral, and ground connections at the terminal block and control board. Tighten any loose screws and reseat push-on connectors.
• 4. Look at power supply section: On the control board, inspect the low-voltage power supply components (transformer or switching supply, capacitors, fuses). A blown board fuse or burnt component indicates the board should be replaced.
• 5. Surge protection: After repair, use a quality surge protector to protect the brewer from future power anomalies.

Warning: Do not bypass fuses or safety devices. If fuses continue to blow, there is an underlying fault that must be diagnosed.