Refrigerator

Not Defrosting

Click on the Steps below to jump directly to that section:

Step 1
1
Ohm defrost heater and sensor circuits from the main PCB.
Step 2
2
If the defrost heater tests open from Main PCB then test directly at components.
Step 3
3
If heater and sensor circuits read good check for voltage using test mode.
Step 4
Step
Always check for possible service bulletins related to defrost issues. (Use LGTA App or GSFS for Service Bulletins).

**NOTICE**

Wiring Colors, Connectors, and Pins will vary by model/product code. Always be sure to download and use the service manual for your specific model.

For Test Mode procedures use this link and input your specific model: https://lgtestmodes.com/

Step 1

Ohm the defrost heater and defrost sensor circuits from the main PCB.

Consult the wiring diagram of the model you are working on to verify proper connector & wire colors.

To check continuity of the defrost circuit unplug the connector from the Main PCB. Insert needle leads on the wire side of the connector (DO NOT INSERT NEEDLE LEADS INTO THE HOLES OF THE CONNECTOR).

Step 2

Test at the Components. 

If the defrost heater or sensor circuits read open from the Main PCB retest directly at the heater and sensor.

(Issue could be an open defrost melting fuse)

Step 3

Test voltage in test mode 3

Now that it is in test mode, check the Main PCB for 120Vac during a forced defrost test (Test mode 3). If the temperature is above 46ºF the test mode will not activate. If the Main PCB does not produce 120Vac then replace the Main PCB.

Step 4

Always check for possible service bulletins related to defrost issues. (Use LGTA App or GSFS for Service Bulletins).