Fridge
ER IS
The ER IS error code on an LG fridge indicates a fault with the ice maker sensor (specifically the ice maker tray thermistor), and while it won’t immediately damage your food, it will stop ice production entirely until resolved.
What does this error mean?
ER IS stands for ‘Ice maker Sensor error’. Your LG fridge continuously monitors the temperature of the ice maker tray using a small thermistor — a temperature-sensing resistor. When the fridge’s control board receives a reading that’s out of expected range, or receives no signal at all, it throws the ER IS code and disables the ice maker as a precaution.
Est. repair cost
£10–£25 DIY thermistor replacement; £80–£150 professional repair including labour
🔍 Likely causes
🛠️ Step-by-step fix
Reset the fridge first: unplug it from the mains for 10–15 minutes, then plug back in. If ER IS clears and the ice maker runs normally, the fault was a temporary sensor glitch.
Defrost the ice maker manually: if you can see heavy ice build-up around the ice maker tray or in the freezer compartment, turn the fridge off and allow it to defrost fully for 24 hours with the doors open. Dry the interior thoroughly before restarting.
Check the ice maker wiring harness: with the fridge unplugged, locate the ice maker at the top of the freezer compartment. Carefully unclip and re-seat the wiring connector that links the ice maker to the back wall. Look for any visible damage to the wires.
Test or replace the ice maker thermistor: the thermistor is a small component clipped onto the ice maker tray. Using a multimeter, test its resistance at room temperature — an LG tray thermistor typically reads around 5kΩ at 25°C. A reading of zero (short) or infinite (open circuit) confirms a failed sensor. Replacement thermistors cost £10–£25 online and are straightforward to swap with basic tools.
If all the above checks out but the error persists, the ice maker assembly itself may need replacing. LG ice maker assemblies for common UK models (e.g. GSJ series) cost £60–£120 as a spare part. This is a DIY-feasible job but requires removing freezer shelving and disconnecting the water supply line — turn off the water feed first.
Do not attempt to test or replace the main control board yourself — this requires professional diagnosis to rule out other faults before an expensive board is purchased.
📞 When to call a professional
Call an engineer if the error returns after a full defrost and reset, or if you’re not confident working around the wiring and water connections inside the freezer compartment. When you call, tell them you have an ER IS code on an LG fridge and that you’ve already attempted a reset and defrost — this saves diagnostic time. An LG-approved engineer or reputable independent appliance repairer is the right choice here.
⚖️ Repair or replace?
A thermistor replacement by a professional will typically cost £80–£130 all-in for labour and parts — well worth it on a fridge under 8 years old. If your LG fridge is over 8–10 years old and the repair quote exceeds £150, replacement becomes more sensible; a comparable LG American-style fridge freezer starts from around £700–£900 new. For fridges under five years old, always repair first.