Which circuit board (PCB) controls detergent/softener dispensers on LG Washer?

Brand: LG
Model Number: WM4500HBA/00
Main Symptom: Dispenser issues, not dispensing, or not notifying that empty

What happens & when: I need to replace the circuit board that controls dispenser functions in my LG Washer. Googling that states to replace the “Main control board or power board, that manages the dispenser functions in the LG washer.”

For this washer, I see two where one is a “Main Power Control Board Assembly”, and another one is the “Power Control Board Assembly”. Which one controls dispenser functions?

Main Power Control Board Assembly: EBR87927901 Washer Main Power Control Board Assembly | Genuine Lg OEM In Stock

Power Control Board Assembly: EBR88051101 Power Control Board Assembly | Genuine Lg OEM In Stock

The main control (EBR87927901) is responsible for operating the water valves, while the power control board (EBR88051101) operates the detergent pumps.

Which specific issue is occurring:

  • Is it the softener, laundry detergent, or bleach not dispensing?

  • Or is water not entering the dispenser housing at all?

If water is reaching the dispenser housing, the next step would be checking for any detergent residue or buildup that could be clogging the dispenser passages. It can also help to listen during operation to see if the dispenser pumps sound like they’re trying to run.

Main control board- EBR87927901 Washer Main Power Control Board Assembly | Genuine Lg OEM In Stock

Power control board- EBR88051101 Power Control Board Assembly | Genuine Lg OEM In Stock