Safety first: Disconnect power at the breaker. Electronic boards are sensitive to static; avoid touching traces and components directly.

Power reset: Turn the breaker off for 5 minutes, then back on. Try to start the dryer again. If E03 returns immediately, continue.
Access control panel: Remove the top panel or console screws (refer to your Monogram model's service layout). Carefully tilt the console forward to expose the user interface and wiring.
Check ribbon cables: Locate the flat ribbon cable(s) between the UI and the main control board. Gently unplug and reinsert them to ensure a solid connection. Look for kinks, tears, or burn marks.
Inspect for moisture/corrosion: Check connectors for signs of moisture, corrosion, or burnt spots. If present, dry the area thoroughly and clean light corrosion with contact cleaner. Severe damage usually requires board replacement.
Test operation: Reassemble the console, restore power, and test. If E03 persists, the UI board or main control board is likely defective and should be replaced, typically by a qualified technician.

Dryer will not start, E03 appears on display, control beeps

Possible Causes