LG Oven F9 Error Code: What It Means and How to Fix It

Last updated: October 5, 2026 · Codes covered: F9 · Sources

Verify in your manual: LG doesn't publish the exact temperature test behind F9, and LG's own pages describe it for electric ranges; gas-model details come from repair sources.

An F9 code on an LG range or wall oven means the upper oven isn't heating properly. Sometimes a simple reset clears it. If it keeps coming back, a part like the bake element (electric) or the igniter (gas) has usually failed, and on gas models that repair belongs to a technician.

What the F9 code means

LG's US error code list says F9 "indicates the Upper Oven Is Not Heating Properly." LG Canada lists F-9 as an electric range code, and repair guides also cover it on LG gas ovens. On a single-oven range, the "upper oven" is simply your oven. On double-oven and double wall oven models, it's the top cavity.

LG doesn't publish the exact temperature test the control uses to decide the oven isn't heating, so we haven't included one here.

F9 is not a door-lock code. You'll see F9 described as a door-lock fault on some sites, but LG's own list gives door-lock errors their own codes:

• F10: door locking system failure (upper oven)
• F20: door locking system failure (lower oven)

Other look-alikes on LG's list:

• F6: upper oven heating error
• F19: oven heating error

These are separate codes. Use your model's owner's manual for the exact code list, because codes vary by model.

Likely causes (most common first)

1. A temporary control glitch, for example after a power blip. LG's first fix is a reset.
2. Gas supply off (gas models). The range's gas shutoff valve is closed, or the house gas supply is interrupted.
3. Burned-out bake element (electric). The element at the bottom of the oven is broken, blistered, or has lost continuity. This is one of the most common reasons an electric oven won't heat.
4. Weak or failed bake igniter (gas). iFixit notes that a worn igniter may never get hot enough to open the gas valve, so the burner never lights.
5. Oven temperature sensor problem. The sensor inside the oven tells the control how hot it is. If it's faulty, the oven may not heat correctly.
6. Loose, burned, or damaged wiring to the element, sensor, or control.
7. Control board fault, such as a relay that no longer powers the bake element or gas valve. That's diagnosed by a technician.

How to fix it, step by step

Try the oven again after each step.

1. Press CLEAR/OFF and try again. This is LG's first step for F9. Start the same bake setting again.
2. Reset the power. If F9 comes back, LG says to turn off the circuit breaker for the range, wait 30 seconds, and turn it back on.
3. Check the gas supply (gas models).
   • Make sure the range's gas shutoff valve, usually behind the range or in a cabinet next to it, is open. The handle should be in line with the pipe.
   • Make sure your cooktop burners light. If none of your gas appliances work, call your gas company.
   • If you smell gas, don't touch anything electrical. Leave the house and call your gas company from outside.
4. Check the breaker (electric models). Make sure the range's breaker hasn't tripped. If it has, switch it fully off, then back on.
5. Look at the bake element (electric). With the oven off and cool, look at the bottom element (on hidden-element models, it's under the oven floor and you may not be able to see it). Breaks, blisters, bubbles, or a burned spot mean it needs replacing.
6. Note what happens on a gas model. During a normal bake, notice whether the oven gets warm at all. Don't open panels or touch any gas part. If it never heats, the bake igniter or gas valve is the likely cause, and that's a technician repair.
7. Test the element and sensor (electric only). If you're comfortable doing it, follow "Test the part" below. If not, or if your range is gas, request service.

Test the part

These checks are for electric LG ranges and wall ovens. On gas ranges, the parts behind F9 are the igniter and gas valve at the oven burner. Don't remove or test those yourself. Call a technician.

1. Turn off the power. Switch off the range's circuit breaker, or pull the range out and unplug it if you can reach the plug. Let the oven cool completely. (Gas models: also turn off the gas at the range's shutoff valve, then stop here and call a pro.)
2. Find the bake element terminals. Depending on the model, you reach them from inside the oven (where the element meets the back wall) or from the back panel, as PartSelect describes. Hidden-element models need the oven floor removed. Check your owner's manual or the parts diagram for your model.
3. Photograph the wires before you disconnect anything, and pull the connectors off by the terminal, not the wire.
4. Check the element for continuity. Set your multimeter to the lowest ohms setting and touch one probe to each terminal.
   • A reading means the element has continuity.
   • "OL" or infinity (open) means the element is broken and needs replacing.
5. Check the oven temperature sensor. This is the thin probe on the inside back wall, usually near the top. Unplug its connector (often reached from inside the oven or from the back) and measure across its two pins at room temperature. An open reading (OL) or a reading near zero (short) points to a bad sensor. LG doesn't publish a public value for the sensor, so check your model's tech sheet for the correct room-temperature reading.
6. Inspect the wiring and terminals. Look for burned, melted, or loose connections on the element, sensor, and connectors you can see.

Swipe the table sideways to see every column.

Stop and call a pro if you can't reach the part, you aren't sure which terminals to test, the parts test fine but F9 keeps coming back (that points to wiring or the control board, which need live tests), or the range is under warranty.

Safety notes

When to call a pro

Request LG service or call a qualified appliance technician if:

• F9 returns after a CLEAR/OFF and a 30-second breaker reset. LG says the unit will then need service.
• It's a gas range and the oven won't heat but the gas supply is on.
• The bake element and sensor test fine, so the problem may be wiring or the control board.
• You see burned wires or scorch marks behind the oven.
• The range is under warranty. Check your coverage before you open any panels.

You can schedule repair through LG's US support site (Request a Repair).

FAQ

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