GE undercounter ice maker displays E0 and stops making ice or will not start a cycle.

Safety first: Unplug the ice maker or switch off the circuit breaker before removing any panels. Water and electricity together are dangerous.

• Power reset: Disconnect power for 5 minutes, then restore power to see if the E0 code clears. Sometimes a transient communication error will reset.
• Check harness connections: Remove the front kick plate or top cover (model dependent). Locate the main control board and user interface board. Inspect all wire harness plugs for being fully seated and free of corrosion or burn marks. Reseat each connector firmly.
• Inspect for moisture damage: Look for signs of condensation or water intrusion on the control board area. If present, dry the area thoroughly and correct any visible leaks before reassembly.
• Test operation: Restore power and run a test cycle. If E0 returns immediately, the main control board or UI board is likely defective.
• When to call a technician: If wiring is intact and the code persists, replacement of the main control board should be done by a qualified technician to avoid miswiring or ESD damage.