How do I fix error code E CO on my LG LL31H6530S?

1. undefined: Check all harness connections between main PCB and display PCB for looseness, especially hinge wiring. 2. undefined: Check voltage at CON101 pins 18–16; expected 12V. If not 12V, check hinge wiring (loose connection). If hinge is OK but voltage is wrong, replace Main PCB. 3. undefined: Check voltage at CON101 pins 10–16; expected 5V. If not 5V, check hinge connection. If hinge OK, replace Main PCB. 4. undefined: Check voltage at CON101 pins 14–16; expected 0V or 5V (not between). If not correct, replace Display PCB. 5. undefined: Check voltage at CON101 pins 12–16; expected 0V or 5V. If not correct, replace Main PCB. 6. undefined: Check voltage at CON5 pins 4–3; expected 0V or 5V. If not correct, replace Display PCB. 7. undefined: Check voltage at CON5 pins 5–3; expected 0V or 5V. If not correct, replace Main PCB. 8. undefined: If all checks are within spec, explain to customer.

LG LL31H6530SRefrigerator

Error Code E CO

Communication error between Main MICOM and Display MICOM

Moderate

Address soon - your appliance may not work properly

How to Fix

1
Check all harness connections between main PCB and display PCB for looseness, especially hinge wiring.
2
Check voltage at CON101 pins 18–16; expected 12V. If not 12V, check hinge wiring (loose connection). If hinge is OK but voltage is wrong, replace Main PCB.
3
Check voltage at CON101 pins 10–16; expected 5V. If not 5V, check hinge connection. If hinge OK, replace Main PCB.
4
Check voltage at CON101 pins 14–16; expected 0V or 5V (not between). If not correct, replace Display PCB.
5
Check voltage at CON101 pins 12–16; expected 0V or 5V. If not correct, replace Main PCB.
6
Check voltage at CON5 pins 4–3; expected 0V or 5V. If not correct, replace Display PCB.
7
Check voltage at CON5 pins 5–3; expected 0V or 5V. If not correct, replace Main PCB.
8
If all checks are within spec, explain to customer.