Unit shows E4 and shuts down; may attempt to start then stop repeatedly.

Safety first: Unplug the ice maker before accessing the evaporator or internal components. Water and electricity are a dangerous combination.

• Step 1 – Inspect evaporator for ice buildup: Remove the ice bin and front cover to view the evaporator plate/coil. Look for heavy frost or solid ice accumulation.
• Step 2 – Manually defrost if needed: If there is heavy ice, leave the unit unplugged with the door open for several hours until all ice melts. Place towels to catch water. Do not chip ice with sharp tools to avoid damaging the evaporator.
• Step 3 – Check drain system: Verify that the drain trough and drain hose are clear. Flush with hot water to remove any blockage. A clogged drain can cause water to refreeze on the evaporator.
• Step 4 – Verify thermistor placement: Ensure the evaporator thermistor is firmly clipped to the correct location on the evaporator and has good thermal contact. Reposition if loose.
• Step 5 – Test thermistor: Measure resistance at known temperatures and compare to GE specs. Replace the thermistor if readings are out of range.
• Step 6 – Control board evaluation: If the thermistor and drainage are correct and E4 returns, the control board may be misinterpreting temperature data and should be replaced.