F4 Moderate Moderate DIY

LG Range F4 — Lower Oven Thermistor Error

LG Oven · Error code F4

What F4 Means

F4 means the lower oven temperature sensor (thermistor) is reading out of range (double-oven models).

Symptoms

  • Lower oven heats incorrectly
  • F4 on the display

Common Causes

1
Failed lower thermistor

The lower oven temperature sensor has failed.

2
Sensor wiring fault

A damaged lower sensor harness.

How to Fix It

  1. Reset at the breaker for 30 seconds.
  2. Test the lower oven sensor resistance and check wiring; replace if out of spec.

Parts You May Need

If diagnosis points to a failed part, these are the common replacements. As an Amazon Associate we earn from qualifying purchases.

Common replacement LG Oven Temperature Sensor View on Amazon→

More LG Oven Codes

5b 5b — Sabbath Mode active (not a fault) CF1 CF1 — Left-front cooktop sensor open/short CF2 CF2 — Left-rear cooktop sensor open/short CF3 CF3 — Right-front cooktop sensor open/short CF4 CF4 — Right-rear cooktop sensor open/short F1 Range F1 — Upper Oven Thermistor Error

All LG codes → All oven codes →

Always unplug an appliance before servicing it. This guide is for informational purposes and is not a substitute for a qualified technician.