Component guide

Main control board

Coordinates sensors, relays, motors and user inputs.

What it does

Coordinates sensors, relays, motors and user inputs.

Symptoms that can involve this component

Multiple unrelated faults, communication codes, dead/erratic control.

Other causes that can look similar

Power supply, connector, peripheral fault, software/control board. Diagnose other causes before condemning the board.

Homeowner-safe observations

Record the exact error code, when it occurs, noises, visible water/frost, and whether the problem is consistent. Use only user-accessible filters, vents, hoses or controls described in the owner manual.

When service is appropriate

Internal electrical measurements, energized testing, gas work, sealed refrigeration work and component replacement should be handled according to the manufacturer service information by a competent person.

Understand part-number terminology