Frigidaire Oven F31 Error Code Troubleshooting Guide

Here’s the straight factory path: find out if the temp sensor, the wiring, or the control board is shorted, then replace the bad piece.

1. Kill power first (non‑negotiable)

• Go to the breaker panel.
• Shut off the range/oven breaker (usually two tied 40–50A breakers).
• Confirm the display is dead. No beeps, no lights. This is 240V. Don’t play with it live.

2. Try the quick reset

• Leave power off for 5 minutes.
• Turn breaker back on.
• If F31 vanished and doesn’t come back after heating the oven, it was likely a glitch. If it pops right back up, keep going.

3. Find the oven temperature sensor

• Open the oven door.
• Look at the back wall inside the oven: thin metal rod, usually top center or top-left, held by two screws. That’s the sensor probe.
• Remove the two screws. Gently pull the sensor tip toward you; there’s a wire and connector behind it.

4. Check the connector and wiring for an obvious short

• With power still off, unplug the small connector for the sensor.
• Look for:
• • Burnt or melted plastic.
  • Bare copper showing or two conductors touching.
  • Water/steam in the connector (common after self‑clean or big boil‑overs).
• If it’s wet, dry it out: towel + let it sit, or gently blow with a hair dryer on low (don’t melt it).
• If insulation is cooked or wires are fused together, that’s your short. You’ll need to repair or replace that harness section.

5. Ohm‑test the temperature sensor (this is the main suspect)

• You need a basic multimeter that reads ohms (Ω).
• Disconnect the sensor from the harness so it’s loose in your hand.
• Set meter to the 2kΩ (or similar) range.
• Touch one meter lead to each sensor pin.
• At room temp (~70°F / 21°C) a good Frigidaire sensor is usually around 1050–1100 Ω.
• Bad readings for F31:
• • Very low (like under 500 Ω).
  • Close to 0 Ω (meter basically reads a short).
  • Meter doesn’t settle and jumps around crazy.
• If it’s shorted or way out of range, replace the sensor. That’s the official first fix.

6. If the sensor tests good, chase the harness

• With the sensor still unplugged, pull the range out from the wall (have someone help; don’t scratch the floor).
• Unplug the whole range cord from the wall for safety.
• Remove the rear cover panel to access the main wiring and the control board (clock/timer board).
• Find the two wires that run from the oven sensor connector to the control board plug labeled something like SENSOR or marked with sensor terminals.
• Look for:
• • Pinched spots where the harness runs past sharp metal.
  • Burned insulation.
  • Places where the two sensor wires are rubbed through and touching.
• If you see a short, repair with high‑temp wire and proper high‑temp wire nuts or replace that harness section.

7. Rule in / rule out the control board

• With the range still unplugged, disconnect the sensor wires from the control board.
• Measure resistance across the sensor terminals on the board side of the harness (not the sensor itself):
• • If you read near 0 Ω with the sensor unplugged, the harness is shorted somewhere. Fix or replace harness.
  • If it reads open (OL) with sensor unplugged, harness is probably okay.
• Now plug the good‑tested sensor back into the harness and measure again at the control board terminals:
• • If you now read ~1050–1100 Ω and still get F31 when powered up, the control board’s sensor circuit is bad. Replace the control board (EOC/ERC).

8. Reassemble and test

• Button everything back up. Make sure no wires are touching bare metal.
• Plug the range back in and reset the breaker.
• Clear the error if needed, then start Bake at a low temp and see if F31 stays gone.