LG Oven Error Codes — F1, F2, F3, F4, F5, F7, F9, tE, SE/5E, CE Complete Guide

Common Symptoms

• Error code displayed on LG oven panel or ThinQ app (F1, F2, F3, F4, F5, F7, F9, tE, SE, 5E, CE)
• Oven not heating — error code on display at startup or during preheat
• LG oven door locked after self-clean and will not open — F5 or F9 displayed
• SE or 5E code — control panel buttons erratic or completely unresponsive
• Oven temperature overshooting or running away — F3 displayed during baking
• Dual-fuel LG range — gas burners work normally but electric oven will not heat
• Error code clears after unplug but returns after one or two cycles

Most Likely Causes

1. 1

   F1 — Oven Temperature Sensor Open Circuit

   F1 means the oven cavity temperature sensor (NTC thermistor, MCK49849603) is reading an open circuit — resistance so high the board cannot interpret a temperature. Cause: the sensor probe has burned out internally, or the wiring harness from the sensor to the control board has a broken wire or disconnected connector. The sensor is mounted in the upper-rear corner of the oven cavity with 2 screws and connects via a 2-wire harness. Test: unplug the oven, remove the sensor from inside the oven cavity, disconnect the 2-wire connector on the sensor lead, measure resistance across the two terminals — should read approximately 1,080Ω at room temperature. OL = open, replace MCK49849603. LG ThinQ app on app-connected models (LSE4611ST, LSGL6335F) will display F1 in the appliance status and may record the fault timestamp.

2. 2

   F2 — Oven Temperature Sensor Short Circuit

   F2 is the opposite of F1: the oven sensor is reading a short circuit — resistance near zero, indicating the two sensor wires are touching or the thermistor bead has internally shorted. MCK49849603 at room temperature should read ~1,080Ω. A reading below 500Ω indicates a shorted or degraded sensor. Also check: if the sensor wires are routed through a metal panel grommet and the insulation has worn through, the wires can short to the chassis and trigger F2 even with a good sensor. Inspect the wiring harness from the sensor to the control board for any pinched or chafed sections before replacing the sensor.

3. 3

   F3 — Oven Runaway Temperature (Critical)

   F3 means the oven temperature has exceeded the safe operating limit — the control board has detected that the oven is significantly hotter than the set point and the element or burner is still on. This is the most critical LG oven code: a relay on the control board stuck closed means the bake or broil element is getting continuous power regardless of the thermostat command. Immediate action: turn off the oven at the breaker. Do not use the oven until the fault is diagnosed. Test: after the oven cools, power it up and start a bake cycle at 350°F — monitor actual oven temperature with an independent oven thermometer. If the oven overshoots 350°F by more than 50–75°F and keeps climbing, a relay on the control board is stuck. The board must be replaced. Also check the oven temperature sensor (MCK49849603) — if the sensor is reading falsely low, the board will command more heat to compensate, producing a runaway condition without a stuck relay.

4. 4

   F4 — Oven Temperature Sensor Out of Range

   F4 indicates the oven sensor is connected and functional but returning a value outside the expected measurement range. Typically seen when a non-LG replacement sensor with the wrong resistance curve is installed, or when the sensor is partially degraded and reading correctly at room temp but drifting at high temperatures. Test the sensor at room temperature (1,040–1,120Ω is the acceptable range for MCK49849603). Also test with a heat gun — the resistance should decrease gradually and predictably as temperature rises. An erratic or non-linear response indicates a degraded sensor that is failing intermittently.

5. 5

   F5 — Door Latch Motor Failure (Critical After Self-Clean)

   F5 indicates the door latch assembly has not completed its travel — either failed to lock during self-clean initiation or stuck locked after self-clean completion. Door latch motor MHI61892401 is a small electric motor that drives a cam to lock and unlock the oven door. Self-clean cycles run the oven at 900°F+ — the thermal stress degrades the latch motor over time. F5 is the most common LG oven code after a self-clean cycle. The diagnosis is identical to Samsung E-08 (same class of failure). Critical: do NOT force the door open if the oven just completed a self-clean cycle — the cavity may still be above 400°F. Wait for full cool-down (at least 1–2 hours) before any manual latch release attempt.

6. 6

   F7 — Stuck Key / Touchpad Short

   F7 means the control board is receiving a continuous pressed-button signal from the touchpad — one key in the membrane matrix is making constant contact. On LG glass cooktop models (LSE4611ST, LSGL6335F), the LG glass surface panel covers the touchpad — food spills, grease, or moisture that seeps under the glass or into the touchpad seam can bridge a contact and trigger F7 without the touchpad itself being failed. Standard diagnosis: (1) Unplug 5 minutes for a hard board reset. (2) Clean the cooktop glass and control panel area thoroughly with a dry cloth — remove any liquid or residue near the control seam. (3) Allow to dry completely before powering up. If F7 clears after cleaning and stays clear, the spill was the cause. If F7 returns after cleaning, the touchpad membrane must be replaced.

7. 7

   F9 — Door Lock Relay Fault / tE — Sensor Fault / SE — Touchpad Fault / CE — Comm Error

   F9 indicates a door lock relay fault on the control board — the board is commanding the door lock but the circuit is not responding correctly. Different from F5 (which is the latch motor mechanism) — F9 points to the electrical circuit driving the latch, while F5 is the motor or latch position switch. tE (temperature error) is an alternative display format for sensor faults — same root cause as F1/F2, same test procedure (MCK49849603, ~1,080Ω at room temp). SE or 5E on LG ovens is the touchpad short code — same as F7 on some model firmware versions. CE indicates a control board communication fault — the main board and display board or secondary control module have lost communication. CE can result from a loose ribbon cable connector, a power surge, or a failed display board.

Quick DIY Checks

1. 1Hard reset — always start here for any LG oven code: unplug the range completely from the wall outlet (or turn off the dedicated circuit breaker and leave it off for 5 full minutes). LG oven control boards can get stuck in error loops — a hard 5-minute power removal clears the board memory and often resolves transient F1, tE, SE, and CE codes. After restoring power, watch the display during startup — does the code appear immediately or only after running a bake cycle? Codes that appear immediately on startup are persistent faults requiring part diagnosis. Codes that appear only during operation are intermittent faults — note the exact operating conditions when the code appears (preheat, 350°F bake, broil, self-clean) as this narrows the diagnosis significantly. For LG ThinQ-connected models, check the ThinQ app under Appliances → your range → Diagnose to see fault history.
2. 2Test the oven temperature sensor (MCK49849603) — F1, F2, F4, tE codes: unplug the oven. Open the oven door. The sensor probe is located in the upper-rear corner of the oven cavity — a thin metal tube approximately 6 inches long, mounted with 2 Phillips screws to the back wall. Remove the 2 screws and pull the sensor out of the cavity. The wiring harness connector is inside the cavity (pull 2–3 inches of slack through the mounting hole to reach it). Disconnect the 2-wire connector. Set multimeter to resistance (Ω). Probe both sensor leads at room temperature — functional MCK49849603 reads 1,040–1,120Ω. OL (no continuity) = open circuit, F1. Below 500Ω = shorted, F2. Reading in range but code persists = check wiring harness from sensor to control board for pinched or burned insulation. Install new MCK49849603 by feeding the lead wire back through the wall opening and threading the 2 mounting screws into the oven back panel — do not overtighten on the ceramic-coated oven wall.
3. 3F5 door latch motor diagnosis and manual release — MHI61892401: F5 after self-clean is the most common field call on LG ovens. First priority: confirm oven temperature is below 300°F before touching the door or latch mechanism. Touch the outer door glass — if it is hot enough to be uncomfortable, wait. After cool-down: try the Clear/Off button and attempt normal door opening. On ThinQ models, try initiating a power cycle from the app. If the door remains locked after power cycling, locate the manual latch release. On LG freestanding ranges, the latch mechanism is accessible from above the oven cavity by removing the rear top panel (2–4 screws at the back of the range top). Use a flat-blade screwdriver to manually rotate the latch cam to the unlocked position — the cam slot is visible on the latch motor shaft. Once the door is open, test the latch motor MHI61892401: disconnect the motor connector and measure resistance — should read 200–500Ω across the motor coil terminals. OL = failed motor, replace. Also inspect the door lock position switch (microswitch on the latch assembly) — it should click audibly as the latch cam passes through the locked position.

1. 4F7 / SE stuck key — diagnosis and spill cleaning procedure: on LG glass cooktop ranges (LSE4611ST, LSGL6335F), the entire cooktop glass surface is one piece — control panel inputs are capacitive touch zones under the glass. A single spilled liquid near the control zone can trigger F7. Cleaning procedure: unplug the range. Use a dry microfiber cloth to wipe the entire cooktop glass, paying special attention to the control panel zone along the front edge. Use a toothpick or soft brush to clean any residue from the edge seam where the glass meets the frame. Do NOT use abrasive scrubbers on LG glass cooktops — they damage the surface and can affect touch sensor sensitivity. After thorough cleaning, allow 15 minutes to fully dry, then restore power. If F7 still appears after cleaning, disconnect the touchpad ribbon cable from the control board (accessible from behind the control panel — remove the console back cover screws). Power the oven with the ribbon disconnected: if F7 disappears, the touchpad membrane is shorted; if F7 still appears, the control board's scanning circuit is the fault.
2. 5Dual-fuel LG diagnosis — gas burners work, electric oven does not heat (LRGL5825F, LSGL6335F): dual-fuel LG ranges use gas for the cooktop burners and a 240V electric element for the oven. If the gas burners fire normally but the oven will not heat and no error code is displayed, the issue is with the 240V supply to the oven element — not a gas fault. Check: (1) The range is connected to a 240V outlet — dual-fuel ranges require a dedicated 4-wire 240V circuit, not a 120V outlet. (2) Check the circuit breaker — the dual-fuel range breaker is double-pole; trip both poles and reset. A single tripped pole allows 120V to the unit (gas works, controls light up) but oven element gets no power. (3) Inspect the terminal block at the rear of the range — the block connects the 240V supply to the oven element circuit. Burned or loose terminal block lugs will cause oven no-heat with normal gas operation. If an error code IS displayed on the oven panel, return to the F1–F9 diagnostic steps above.
3. 6Test oven temperature accuracy (calibration check) before replacing components — F3, F4: before condemning any parts for temperature-related codes, verify the oven is actually running at the wrong temperature. Purchase an oven thermometer (not the meat probe — a hanging rack thermometer) and place it in the center of the oven cavity. Set the oven to 350°F and allow 20 minutes for full stabilization after the preheat beep. Read the thermometer. LG ovens from the factory are calibrated to within ±25°F — if your reading is between 325°F and 375°F, the oven is within spec. Ovens reading ±35°F or more: LG provides oven calibration adjustment in the Settings menu on most models — can adjust ±35°F from the default. Access: press Settings → Oven Calibration (model-specific menu path). If the oven significantly overshoots (over 400°F when set to 350°F), that is the F3 runaway scenario — control board relay fault, not a calibration issue.
4. 7CE communication fault — ribbon cable and board isolation: CE (control board communication error) points to a lost connection between the main control board and the display board or secondary module. Unplug the oven. On freestanding ranges, remove the console back cover (rear screws). Inspect the ribbon cable(s) connecting the display board to the main control board — the connector locks with a small plastic tab that can loosen from vibration. Press each ribbon cable connector firmly into its socket until you feel the lock click. Also inspect for any visible burn marks on the control board or display board. Restore power and test. If CE returns, disconnect each ribbon cable individually while powered (one at a time, reboot after each) to isolate which cable/board is triggering the fault. CE boards on LG ovens: the display board (front panel assembly) typically runs $40–$100 and is more likely to fail than the main control board. Replace the display board first if all ribbon connections are confirmed good.

Repair vs Replace

Recommended Tools & Parts

• LG Oven Temperature Sensor — MCK49849603

  OEM LG oven cavity temperature sensor (NTC thermistor). Reads 1,040–1,120Ω at room temperature. Fixes F1 (open) and F2 (short) error codes. Located upper-rear corner of oven cavity, 2 mounting screws. Verify model compatibility — MCK49849603 covers LRE3061ST, LSE4611ST, LTE4815ST and related models.

  $20–$40

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• LG Door Latch Motor Assembly — MHI61892401

  Replacement door latch motor for LG self-cleaning ranges and wall ovens. Covers F5 door latch fault — most common after self-clean cycles. Test existing motor: 200–500Ω across motor coil terminals. OL = failed. Covers LRGL5825F, LSE4611ST, LSGL6335F and related models.

  $40–$80

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• LG Range Touchpad / Membrane Keypad

  Replacement touchpad membrane for LG range control panel. Fixes F7 and SE/5E stuck key codes after confirming spill cleaning does not resolve the code. Model-specific — verify by model number. Includes membrane overlay and ribbon cable.

  $50–$120

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• LG Oven Control Board

  Replacement main control board for LG freestanding and slide-in ranges. Required for F3 runaway temperature (stuck relay), CE comm fault (after isolating display board), or F9 door lock relay fault. Replace only after verifying sensor and mechanical components. Model-specific — check part number by model.

  $100–$250

  Buy on Amazon →

• Digital Multimeter

  Required for oven sensor resistance testing (1,080Ω target), door latch motor coil test (200–500Ω), and wiring harness continuity checks. Any meter in the $15–$40 range is adequate for LG oven diagnostics.

  $15–$40

  Buy on Amazon →

• Oven Thermometer

  Hanging rack-style oven thermometer for calibration check before replacing temperature-related components. Verify actual oven temp vs. set point — essential for F3 and F4 diagnosis. Also used to confirm repair success.

  $8–$15

  Buy on Amazon →

Links are Amazon affiliate links (tag: fixitfastai-20). Prices are estimates.

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