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Error code reference

LG Refrigerator Error Code E1

Left compartment sensor (R1) failure

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Left compartment sensor (R1) failure — sensor disconnected or short circuited.

First step from the service manual

Check left compartment lid sensor connector and measure sensor resistance at CON2 on main PCB (normal range 0.5V–4.5V at check point A; 0V = shorted, 5V = open).

The complete diagnostic procedure includes additional test steps, resistance specifications, wiring diagram references, and component test points.

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What E1 means on a LG refrigerator

The E1 error code on an LG refrigerator indicates a failure in the left compartment temperature sensor, designated R1. This sensor is a thermistor-type component responsible for monitoring the internal temperature of the left compartment and feeding that data to the main PCB so the control board can regulate cooling cycles accurately. When the board detects a signal outside the acceptable operating range, it flags the E1 code to alert the technician that the sensor circuit is compromised.

The diagnostic check begins at CON2 on the main PCB, where a check point labeled A should read between 0.5V and 4.5V under normal operating conditions. A reading of 0V at that point indicates the sensor circuit is shorted, meaning current is bypassing the thermistor resistance entirely. A reading of 5V indicates an open circuit, meaning the signal wire is broken or the connector is fully disconnected, and no current is completing the loop through the sensor. Both conditions prevent the board from receiving valid temperature data.

The most common physical causes include a loose or corroded connector at CON2, a broken wire in the sensor harness, physical damage to the thermistor itself from ice buildup or impact, or a failed sensor that has drifted permanently out of range. In some cases the main PCB input circuit can fail and produce similar voltage readings even with a known-good sensor in place, so the sensor should be confirmed faulty before replacing the board.

Source: manufacturer service documentation.

Common causes of E1

  1. 01

    Disconnected sensor connector at CON2

    Wiring / connection

    The wire harness connector for the R1 sensor may have come loose from CON2 on the main PCB, producing a 5V open-circuit reading at check point A. Inspect the connector for proper seating and any signs of backing-out pins.

  2. 02

    Failed or shorted thermistor (R1 sensor)

    Part replacement

    The thermistor itself can fail internally, causing either a short (0V reading) or an open (5V reading) at check point A. If resistance measurement of the sensor is outside the normal range, the sensor requires replacement.

  3. 03

    Damaged or broken sensor wiring harness

    Part replacement

    Wires in the sensor harness can crack, chafe, or break due to freezing temperatures, ice buildup, or physical stress over time. Inspect the full length of the harness for visible damage or continuity breaks.

  4. 04

    Corroded or oxidized connector pins

    Wiring / connection

    Moisture inside the refrigerator compartment can cause corrosion on the sensor connector pins, increasing resistance or breaking the circuit entirely. Check the connector at CON2 for discoloration, pitting, or oxidation and clean or replace as needed.

  5. 05

    Faulty main PCB input circuit

    Part replacement

    If the sensor and harness both test within normal parameters but the voltage at check point A remains at 0V or 5V, the input circuit on the main PCB may have failed. Board replacement is the corrective action in this scenario.

See the test procedure for each cause

Frequently asked questions about E1

What does E1 mean on a LG refrigerator?
E1 on an LG refrigerator indicates a failure in the left compartment temperature sensor, identified as R1. The code is triggered when the main PCB detects a voltage at check point A on CON2 that falls outside the normal 0.5V to 4.5V operating range. A reading of 0V points to a shorted sensor, while 5V points to a disconnected or open circuit. The refrigerator cannot accurately regulate the left compartment temperature while this code is active.
Can I fix the E1 error on my LG refrigerator myself?
Some causes of the E1 error are DIY-friendly, particularly reseating a loose connector at CON2 on the main PCB or inspecting the wiring harness for obvious damage. If the thermistor itself has failed, replacing the R1 sensor is a moderate-difficulty repair that requires accessing the sensor, disconnecting the harness, and installing a compatible replacement part. Main PCB replacement is a more complex repair and is best handled by a qualified technician.
Is it safe to use my LG refrigerator while the E1 code is showing?
Using the refrigerator with an active E1 code carries some risk to food safety because the left compartment temperature is no longer being monitored or controlled accurately. The compartment could run warmer than the set point without triggering a normal cooling response. It is best to address the error promptly and use a standalone thermometer to verify compartment temperatures if you must continue using the unit in the interim.
How much does it cost to repair an E1 error on an LG refrigerator?
Repair costs vary depending on the root cause. If only a connector needs reseating, there may be no parts cost at all, though a service call fee typically ranges from $75 to $150. A replacement R1 thermistor sensor generally costs between $15 and $50 for the part, while a main PCB replacement can range from $150 to $400 or more for parts alone. Labor charges vary by region and technician.
Will resetting my LG refrigerator clear the E1 error code?
A power reset may temporarily clear the E1 code from the display, but if the underlying sensor fault is still present, the code will return once the control board runs its diagnostics again. Resetting is useful as a first step to confirm whether the fault is intermittent, but a permanent fix requires identifying and correcting the cause, whether that is a loose connector, a damaged harness, or a failed sensor or board component.

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