How do I fix error code E Sd on my LG LF29S8330D?

1. undefined: Check loose connections between main PCB and Sub PCB harness; reconnect if loose. 2. undefined: Measure voltage at CON1 (Sub) 8th Pin to 33rd Pin; expected active signal (not fixed 0 or 5V). If fixed 0 or 5V, check Sub PCB connection; if connection is normal, replace Sub PCB. 3. undefined: Measure voltage at CON1 (Sub) 10th Pin to 33rd Pin; expected active signal (not fixed 0 or 5V). If fixed, check Sub PCB connection; if normal, replace Sub PCB. 4. undefined: Measure voltage at CON3 (Main) 1st Pin to 15th Pin; expected active signal (not fixed 0 or 5V). If fixed, check Display PCB connection; if normal, replace Display PCB. 5. undefined: Measure voltage at CON3 (Main) 3rd Pin to 15th Pin; expected active signal (not fixed 0 or 5V). If fixed, check Display PCB connection; if normal, replace Display PCB. 6. undefined: If all checks pass, explain normal operation to customer.

LG LF29S8330DRefrigerator

Error Code E Sd

Sub PCB communication error

Moderate

Address soon - your appliance may not work properly

Also displayed as: E Sd

How to Fix

1
Check loose connections between main PCB and Sub PCB harness; reconnect if loose.
2
Measure voltage at CON1 (Sub) 8th Pin to 33rd Pin; expected active signal (not fixed 0 or 5V). If fixed 0 or 5V, check Sub PCB connection; if connection is normal, replace Sub PCB.
3
Measure voltage at CON1 (Sub) 10th Pin to 33rd Pin; expected active signal (not fixed 0 or 5V). If fixed, check Sub PCB connection; if normal, replace Sub PCB.
4
Measure voltage at CON3 (Main) 1st Pin to 15th Pin; expected active signal (not fixed 0 or 5V). If fixed, check Display PCB connection; if normal, replace Display PCB.
5
Measure voltage at CON3 (Main) 3rd Pin to 15th Pin; expected active signal (not fixed 0 or 5V). If fixed, check Display PCB connection; if normal, replace Display PCB.
6
If all checks pass, explain normal operation to customer.